Complement cascade (Homo sapiens)
From WikiPathways
Description
There are three branches that lead to activation of the complement system: the classical complement pathway, the alternative complement pathway, and the mannose-binding lectin pathway. Complement proteins are always present in the blood and a small percentage spontaneously activate. Innapropriate activation leads to host cell damage, so the activation process is tightly controlled by several regulatory mechanisms. N.B. Originally the larger fragment of Complement Factor 2 (C2) was designated C2a. However, complement scientists decided that the smaller of all C fragments should be designated with an 'a', the larger with a 'b', changing the nomenclature for C2. Recent literature may use the updated nomenclature and refer to the larger C2 fragment as C2b, and refer to the classical C3 convertase as C4bC2b. Throughout this pathway Reactome adheres to the original convention to agree with the current (Feb 2012) Uniprot names for C2 fragments.Original Pathway at Reactome: http://www.reactome.org/PathwayBrowser/#DB=gk_current&FOCUS_SPECIES_ID=48887&FOCUS_PATHWAY_ID=166658
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Bibliography
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- Chen CB, Wallis R.; ''Stoichiometry of complexes between mannose-binding protein and its associated serine proteases. Defining functional units for complement activation.''; PubMed Europe PMC Scholia
- Liu Y, Endo Y, Iwaki D, Nakata M, Matsushita M, Wada I, Inoue K, Munakata M, Fujita T.; ''Human M-ficolin is a secretory protein that activates the lectin complement pathway.''; PubMed Europe PMC Scholia
- Law SK, Levine RP.; ''Interaction between the third complement protein and cell surface macromolecules.''; PubMed Europe PMC Scholia
- Fujita T, Gigli I, Nussenzweig V.; ''Human C4-binding protein. II. Role in proteolysis of C4b by C3b-inactivator.''; PubMed Europe PMC Scholia
- Kuraya M, Ming Z, Liu X, Matsushita M, Fujita T.; ''Specific binding of L-ficolin and H-ficolin to apoptotic cells leads to complement activation.''; PubMed Europe PMC Scholia
- Tsujimura M, Miyazaki T, Kojima E, Sagara Y, Shiraki H, Okochi K, Maeda Y.; ''Serum concentration of Hakata antigen, a member of the ficolins, is linked with inhibition of Aerococcus viridans growth.''; PubMed Europe PMC Scholia
- Hourcade DE, Mitchell L, Kuttner-Kondo LA, Atkinson JP, Medof ME.; ''Decay-accelerating factor (DAF), complement receptor 1 (CR1), and factor H dissociate the complement AP C3 convertase (C3bBb) via sites on the type A domain of Bb.''; PubMed Europe PMC Scholia
- Aleshin AE, DiScipio RG, Stec B, Liddington RC.; ''Crystal structure of C5b-6 suggests structural basis for priming assembly of the membrane attack complex.''; PubMed Europe PMC Scholia
- Campbell WD, Lazoura E, Okada N, Okada H.; ''Inactivation of C3a and C5a octapeptides by carboxypeptidase R and carboxypeptidase N.''; PubMed Europe PMC Scholia
- Daha MR, Fearon DT, Austen KF.; ''C3 requirements for formation of alternative pathway C5 convertase.''; PubMed Europe PMC Scholia
- Rawal N, Pangburn MK.; ''Formation of high affinity C5 convertase of the classical pathway of complement.''; PubMed Europe PMC Scholia
- Alcorlo M, Tortajada A, Rodríguez de Córdoba S, Llorca O.; ''Structural basis for the stabilization of the complement alternative pathway C3 convertase by properdin.''; PubMed Europe PMC Scholia
- Teillet F, Gaboriaud C, Lacroix M, Martin L, Arlaud GJ, Thielens NM.; ''Crystal structure of the CUB1-EGF-CUB2 domain of human MASP-1/3 and identification of its interaction sites with mannan-binding lectin and ficolins.''; PubMed Europe PMC Scholia
- Scharfstein J, Ferreira A, Gigli I, Nussenzweig V.; ''Human C4-binding protein. I. Isolation and characterization.''; PubMed Europe PMC Scholia
- Krisinger MJ, Goebeler V, Lu Z, Meixner SC, Myles T, Pryzdial EL, Conway EM.; ''Thrombin generates previously unidentified C5 products that support the terminal complement activation pathway.''; PubMed Europe PMC Scholia
- DiScipio RG, Davie EW.; ''Characterization of protein S, a gamma-carboxyglutamic acid containing protein from bovine and human plasma.''; PubMed Europe PMC Scholia
- Zacho RM, Jensen L, Terp R, Jensenius JC, Thiel S.; ''Studies of the pattern recognition molecule H-ficolin: specificity and purification.''; PubMed Europe PMC Scholia
- Ziccardi RJ, Dahlback B, Müller-Eberhard HJ.; ''Characterization of the interaction of human C4b-binding protein with physiological ligands.''; PubMed Europe PMC Scholia
- Aoyagi Y, Adderson EE, Rubens CE, Bohnsack JF, Min JG, Matsushita M, Fujita T, Okuwaki Y, Takahashi S.; ''L-Ficolin/mannose-binding lectin-associated serine protease complexes bind to group B streptococci primarily through N-acetylneuraminic acid of capsular polysaccharide and activate the complement pathway.''; PubMed Europe PMC Scholia
- Weiler JM, Daha MR, Austen KF, Fearon DT.; ''Control of the amplification convertase of complement by the plasma protein beta1H.''; PubMed Europe PMC Scholia
- Kjaer TR, Hansen AG, Sørensen UB, Nielsen O, Thiel S, Jensenius JC.; ''Investigations on the pattern recognition molecule M-ficolin: quantitative aspects of bacterial binding and leukocyte association.''; PubMed Europe PMC Scholia
- Lynch NJ, Roscher S, Hartung T, Morath S, Matsushita M, Maennel DN, Kuraya M, Fujita T, Schwaeble WJ.; ''L-ficolin specifically binds to lipoteichoic acid, a cell wall constituent of Gram-positive bacteria, and activates the lectin pathway of complement.''; PubMed Europe PMC Scholia
- Law SK, Lichtenberg NA, Holcombe FH, Levine RP.; ''Interaction between the labile binding sites of the fourth (C4) and fifth (C5) human complement proteins and erythrocyte cell membranes.''; PubMed Europe PMC Scholia
- Gigli I, Fujita T, Nussenzweig V.; ''Modulation of the classical pathway C3 convertase by plasma proteins C4 binding protein and C3b inactivator.''; PubMed Europe PMC Scholia
- Keshi H, Sakamoto T, Kawai T, Ohtani K, Katoh T, Jang SJ, Motomura W, Yoshizaki T, Fukuda M, Koyama S, Fukuzawa J, Fukuoh A, Yoshida I, Suzuki Y, Wakamiya N.; ''Identification and characterization of a novel human collectin CL-K1.''; PubMed Europe PMC Scholia
- Masaki T, Matsumoto M, Nakanishi I, Yasuda R, Seya T.; ''Factor I-dependent inactivation of human complement C4b of the classical pathway by C3b/C4b receptor (CR1, CD35) and membrane cofactor protein (MCP, CD46).''; PubMed Europe PMC Scholia
- Vorup-Jensen T, Petersen SV, Hansen AG, Poulsen K, Schwaeble W, Sim RB, Reid KB, Davis SJ, Thiel S, Jensenius JC.; ''Distinct pathways of mannan-binding lectin (MBL)- and C1-complex autoactivation revealed by reconstitution of MBL with recombinant MBL-associated serine protease-2.''; PubMed Europe PMC Scholia
- Scibek JJ, Plumb ME, Sodetz JM.; ''Binding of human complement C8 to C9: role of the N-terminal modules in the C8 alpha subunit.''; PubMed Europe PMC Scholia
- Alcorlo M, Martínez-Barricarte R, Fernández FJ, Rodríguez-Gallego C, Round A, Vega MC, Harris CL, de Cordoba SR, Llorca O.; ''Unique structure of iC3b resolved at a resolution of 24 Å by 3D-electron microscopy.''; PubMed Europe PMC Scholia
- Dahlbäck B, Smith CA, Müller-Eberhard HJ.; ''Visualization of human C4b-binding protein and its complexes with vitamin K-dependent protein S and complement protein C4b.''; PubMed Europe PMC Scholia
- Goldberger G, Bruns GA, Rits M, Edge MD, Kwiatkowski DJ.; ''Human complement factor I: analysis of cDNA-derived primary structure and assignment of its gene to chromosome 4.''; PubMed Europe PMC Scholia
- Honoré C, Rørvig S, Hummelshøj T, Skjoedt MO, Borregaard N, Garred P.; ''Tethering of Ficolin-1 to cell surfaces through recognition of sialic acid by the fibrinogen-like domain.''; PubMed Europe PMC Scholia
- Lehto T, Morgan BP, Meri S.; ''Binding of human and rat CD59 to the terminal complement complexes.''; PubMed Europe PMC Scholia
- Sim RB, Reboul A, Arlaud GJ, Villiers CL, Colomb MG.; ''Interaction of 125I-labelled complement subcomponents C-1r and C-1s with protease inhibitors in plasma.''; PubMed Europe PMC Scholia
- Kalant D, Cain SA, Maslowska M, Sniderman AD, Cianflone K, Monk PN.; ''The chemoattractant receptor-like protein C5L2 binds the C3a des-Arg77/acylation-stimulating protein.''; PubMed Europe PMC Scholia
- Davis AE, Harrison RA, Lachmann PJ.; ''Physiologic inactivation of fluid phase C3b: isolation and structural analysis of C3c, C3d,g (alpha 2D), and C3g.''; PubMed Europe PMC Scholia
- Kishore U, Ghai R, Greenhough TJ, Shrive AK, Bonifati DM, Gadjeva MG, Waters P, Kojouharova MS, Chakraborty T, Agrawal A.; ''Structural and functional anatomy of the globular domain of complement protein C1q.''; PubMed Europe PMC Scholia
- Ziccardi RJ, Cooper NR.; ''Activation of C1r by proteolytic cleavage.''; PubMed Europe PMC Scholia
- Teh C, Le Y, Lee SH, Lu J.; ''M-ficolin is expressed on monocytes and is a lectin binding to N-acetyl-D-glucosamine and mediates monocyte adhesion and phagocytosis of Escherichia coli.''; PubMed Europe PMC Scholia
- Jokiranta TS, Cheng ZZ, Seeberger H, Jòzsi M, Heinen S, Noris M, Remuzzi G, Ormsby R, Gordon DL, Meri S, Hellwage J, Zipfel PF.; ''Binding of complement factor H to endothelial cells is mediated by the carboxy-terminal glycosaminoglycan binding site.''; PubMed Europe PMC Scholia
- Butkowski RJ, Elion J, Downing MR, Mann KG.; ''Primary structure of human prethrombin 2 and alpha-thrombin.''; PubMed Europe PMC Scholia
- Fearon DT.; ''Regulation of the amplification C3 convertase of human complement by an inhibitory protein isolated from human erythrocyte membrane.''; PubMed Europe PMC Scholia
- Bokisch VA, Müller-Eberhard HJ.; ''Anaphylatoxin inactivator of human plasma: its isolation and characterization as a carboxypeptidase.''; PubMed Europe PMC Scholia
- Bhakdi S, Käflein R, Halstensen TS, Hugo F, Preissner KT, Mollnes TE.; ''Complement S-protein (vitronectin) is associated with cytolytic membrane-bound C5b-9 complexes.''; PubMed Europe PMC Scholia
- Teillet F, Dublet B, Andrieu JP, Gaboriaud C, Arlaud GJ, Thielens NM.; ''The two major oligomeric forms of human mannan-binding lectin: chemical characterization, carbohydrate-binding properties, and interaction with MBL-associated serine proteases.''; PubMed Europe PMC Scholia
- Dahlbäck B, Stenflo J.; ''High molecular weight complex in human plasma between vitamin K-dependent protein S and complement component C4b-binding protein.''; PubMed Europe PMC Scholia
- Müller-Eberhard HJ.; ''Molecular organization and function of the complement system.''; PubMed Europe PMC Scholia
- Gasque P.; ''Complement: a unique innate immune sensor for danger signals.''; PubMed Europe PMC Scholia
- Sheehan M, Morris CA, Pussell BA, Charlesworth JA.; ''Complement inhibition by human vitronectin involves non-heparin binding domains.''; PubMed Europe PMC Scholia
- Nagasawa S, Ichihara C, Stroud RM.; ''Cleavage of C4b by C3b inactivator: production of a nicked form of C4b, C4b', as an intermediate cleavage product of C4b by C3b inactivator.''; PubMed Europe PMC Scholia
- Kishore U, Reid KB.; ''C1q: structure, function, and receptors.''; PubMed Europe PMC Scholia
- Nonaka M, Yoshizaki F.; ''Evolution of the complement system.''; PubMed Europe PMC Scholia
- Matsumoto AK, Martin DR, Carter RH, Klickstein LB, Ahearn JM, Fearon DT.; ''Functional dissection of the CD21/CD19/TAPA-1/Leu-13 complex of B lymphocytes.''; PubMed Europe PMC Scholia
- Garlatti V, Martin L, Lacroix M, Gout E, Arlaud GJ, Thielens NM, Gaboriaud C.; ''Structural insights into the recognition properties of human ficolins.''; PubMed Europe PMC Scholia
- Farries TC, Lachmann PJ, Harrison RA.; ''Analysis of the interactions between properdin, the third component of complement (C3), and its physiological activation products.''; PubMed Europe PMC Scholia
- Tschopp J, Chonn A, Hertig S, French LE.; ''Clusterin, the human apolipoprotein and complement inhibitor, binds to complement C7, C8 beta, and the b domain of C9.''; PubMed Europe PMC Scholia
- Wu J, Wu YQ, Ricklin D, Janssen BJ, Lambris JD, Gros P.; ''Structure of complement fragment C3b-factor H and implications for host protection by complement regulators.''; PubMed Europe PMC Scholia
- Fearon DT, Austen KF.; ''Initiation of C3 cleavage in the alternative complement pathway.''; PubMed Europe PMC Scholia
- Wittenborn T, Thiel S, Jensen L, Nielsen HJ, Jensenius JC.; ''Characteristics and biological variations of M-ficolin, a pattern recognition molecule, in plasma.''; PubMed Europe PMC Scholia
- Budayova-Spano M, Lacroix M, Thielens NM, Arlaud GJ, Fontecilla-Camps JC, Gaboriaud C.; ''The crystal structure of the zymogen catalytic domain of complement protease C1r reveals that a disruptive mechanical stress is required to trigger activation of the C1 complex.''; PubMed Europe PMC Scholia
- Ma YG, Cho MY, Zhao M, Park JW, Matsushita M, Fujita T, Lee BL.; ''Human mannose-binding lectin and L-ficolin function as specific pattern recognition proteins in the lectin activation pathway of complement.''; PubMed Europe PMC Scholia
- Matsushita M, Kuraya M, Hamasaki N, Tsujimura M, Shiraki H, Fujita T.; ''Activation of the lectin complement pathway by H-ficolin (Hakata antigen).''; PubMed Europe PMC Scholia
- Petersen SV, Thiel S, Jensenius JC.; ''The mannan-binding lectin pathway of complement activation: biology and disease association.''; PubMed Europe PMC Scholia
- Preissner KP, Podack ER, Müller-Eberhard HJ.; ''SC5b-7, SC5b-8 and SC5b-9 complexes of complement: ultrastructure and localization of the S-protein (vitronectin) within the macromolecules.''; PubMed Europe PMC Scholia
- Ross GD, Lambris JD, Cain JA, Newman SL.; ''Generation of three different fragments of bound C3 with purified factor I or serum. I. Requirements for factor H vs CR1 cofactor activity.''; PubMed Europe PMC Scholia
- Huang Y, Fedarovich A, Tomlinson S, Davies C.; ''Crystal structure of CD59: implications for molecular recognition of the complement proteins C8 and C9 in the membrane-attack complex.''; PubMed Europe PMC Scholia
- Pangburn MK, Schreiber RD, Müller-Eberhard HJ.; ''Human complement C3b inactivator: isolation, characterization, and demonstration of an absolute requirement for the serum protein beta1H for cleavage of C3b and C4b in solution.''; PubMed Europe PMC Scholia
- Lehto T, Meri S.; ''Interactions of soluble CD59 with the terminal complement complexes. CD59 and C9 compete for a nascent epitope on C8.''; PubMed Europe PMC Scholia
- Hadders MA, Bubeck D, Roversi P, Hakobyan S, Forneris F, Morgan BP, Pangburn MK, Llorca O, Lea SM, Gros P.; ''Assembly and regulation of the membrane attack complex based on structures of C5b6 and sC5b9.''; PubMed Europe PMC Scholia
- Krych-Goldberg M, Hauhart RE, Subramanian VB, Yurcisin BM, Crimmins DL, Hourcade DE, Atkinson JP.; ''Decay accelerating activity of complement receptor type 1 (CD35). Two active sites are required for dissociating C5 convertases.''; PubMed Europe PMC Scholia
- Schmidt BZ, Colten HR.; ''Complement: a critical test of its biological importance.''; PubMed Europe PMC Scholia
- Schreiber RD, Pangburn MK, Lesavre PH, Müller-Eberhard HJ.; ''Initiation of the alternative pathway of complement: recognition of activators by bound C3b and assembly of the entire pathway from six isolated proteins.''; PubMed Europe PMC Scholia
- Kerr MA.; ''The human complement system: assembly of the classical pathway C3 convertase.''; PubMed Europe PMC Scholia
- Lesavre PH, Müller-Eberhard HJ.; ''Mechanism of action of factor D of the alternative complement pathway.''; PubMed Europe PMC Scholia
- Huang Y, Smith CA, Song H, Morgan BP, Abagyan R, Tomlinson S.; ''Insights into the human CD59 complement binding interface toward engineering new therapeutics.''; PubMed Europe PMC Scholia
- Fujita T, Matsushita M, Endo Y.; ''The lectin-complement pathway--its role in innate immunity and evolution.''; PubMed Europe PMC Scholia
- Ponnuraj K, Xu Y, Macon K, Moore D, Volanakis JE, Narayana SV.; ''Structural analysis of engineered Bb fragment of complement factor B: insights into the activation mechanism of the alternative pathway C3-convertase.''; PubMed Europe PMC Scholia
- Neth O, Jack DL, Dodds AW, Holzel H, Klein NJ, Turner MW.; ''Mannose-binding lectin binds to a range of clinically relevant microorganisms and promotes complement deposition.''; PubMed Europe PMC Scholia
- Mold C, Medof ME.; ''C3 nephritic factor protects bound C3bBb from cleavage by factor I and human erythrocytes.''; PubMed Europe PMC Scholia
- Podack ER, Tschoop J, Müller-Eberhard HJ.; ''Molecular organization of C9 within the membrane attack complex of complement. Induction of circular C9 polymerization by the C5b-8 assembly.''; PubMed Europe PMC Scholia
- Morgan HP, Schmidt CQ, Guariento M, Blaum BS, Gillespie D, Herbert AP, Kavanagh D, Mertens HD, Svergun DI, Johansson CM, Uhrín D, Barlow PN, Hannan JP.; ''Structural basis for engagement by complement factor H of C3b on a self surface.''; PubMed Europe PMC Scholia
- Seya T, Atkinson JP.; ''Functional properties of membrane cofactor protein of complement.''; PubMed Europe PMC Scholia
- Harris CL, Pettigrew DM, Lea SM, Morgan BP.; ''Decay-accelerating factor must bind both components of the complement alternative pathway C3 convertase to mediate efficient decay.''; PubMed Europe PMC Scholia
- Brodbeck WG, Liu D, Sperry J, Mold C, Medof ME.; ''Localization of classical and alternative pathway regulatory activity within the decay-accelerating factor.''; PubMed Europe PMC Scholia
- MUELLER-EBERHARD HJ, LEPOW IH.; ''C'1 ESTERASE EFFECT ON ACTIVITY AND PHYSICOCHEMICAL PROPERTIES OF THE FOURTH COMPONENT OF COMPLEMENT.''; PubMed Europe PMC Scholia
- Nagasawa S, Stroud RM.; ''Cleavage of C2 by C1s into the antigenically distinct fragments C2a and C2b: demonstration of binding of C2b to C4b.''; PubMed Europe PMC Scholia
- Troegeler A, Lugo-Villarino G, Hansen S, Rasolofo V, Henriksen ML, Mori K, Ohtani K, Duval C, Mercier I, Bénard A, Nigou J, Hudrisier D, Wakamiya N, Neyrolles O.; ''Collectin CL-LK Is a Novel Soluble Pattern Recognition Receptor for Mycobacterium tuberculosis.''; PubMed Europe PMC Scholia
- Müller-Eberhard HJ, Polley MJ, Calcott MA.; ''Formation and functional significance of a molecular complex derived from the second and the fourth component of human complement.''; PubMed Europe PMC Scholia
- Pangburn MK, Schreiber RD, Müller-Eberhard HJ.; ''Formation of the initial C3 convertase of the alternative complement pathway. Acquisition of C3b-like activities by spontaneous hydrolysis of the putative thioester in native C3.''; PubMed Europe PMC Scholia
- Gerard NP, Gerard C.; ''The chemotactic receptor for human C5a anaphylatoxin.''; PubMed Europe PMC Scholia
- Garlatti V, Martin L, Gout E, Reiser JB, Fujita T, Arlaud GJ, Thielens NM, Gaboriaud C.; ''Structural basis for innate immune sensing by M-ficolin and its control by a pH-dependent conformational switch.''; PubMed Europe PMC Scholia
- Weis JJ, Tedder TF, Fearon DT.; ''Identification of a 145,000 Mr membrane protein as the C3d receptor (CR2) of human B lymphocytes.''; PubMed Europe PMC Scholia
- Medicus RG, Götze O, Müller-Eberhard HJ.; ''Alternative pathway of complement: recruitment of precursor properdin by the labile C3/C5 convertase and the potentiation of the pathway.''; PubMed Europe PMC Scholia
- Barilla-LaBarca ML, Liszewski MK, Lambris JD, Hourcade D, Atkinson JP.; ''Role of membrane cofactor protein (CD46) in regulation of C4b and C3b deposited on cells.''; PubMed Europe PMC Scholia
- Becherer JD, Lambris JD.; ''Identification of the C3b receptor-binding domain in third component of complement.''; PubMed Europe PMC Scholia
- Matsushita M, Endo Y, Fujita T.; ''Cutting edge: complement-activating complex of ficolin and mannose-binding lectin-associated serine protease.''; PubMed Europe PMC Scholia
- Hajela K, Kojima M, Ambrus G, Wong KH, Moffatt BE, Ferluga J, Hajela S, Gál P, Sim RB.; ''The biological functions of MBL-associated serine proteases (MASPs).''; PubMed Europe PMC Scholia
- Sepp A, Dodds AW, Anderson MJ, Campbell RD, Willis AC, Law SK.; ''Covalent binding properties of the human complement protein C4 and hydrolysis rate of the internal thioester upon activation.''; PubMed Europe PMC Scholia
- Cain SA, Monk PN.; ''The orphan receptor C5L2 has high affinity binding sites for complement fragments C5a and C5a des-Arg(74).''; PubMed Europe PMC Scholia
- Kinoshita T, Medof ME, Nussenzweig V.; ''Endogenous association of decay-accelerating factor (DAF) with C4b and C3b on cell membranes.''; PubMed Europe PMC Scholia
- Garlatti V, Belloy N, Martin L, Lacroix M, Matsushita M, Endo Y, Fujita T, Fontecilla-Camps JC, Arlaud GJ, Thielens NM, Gaboriaud C.; ''Structural insights into the innate immune recognition specificities of L- and H-ficolins.''; PubMed Europe PMC Scholia
- Ziccardi RJ, Cooper NR.; ''Physicochemical and functional characterization of the C1r subunit of the first complement component.''; PubMed Europe PMC Scholia
- Pangburn MK, Müller-Eberhard HJ.; ''Kinetic and thermodynamic analysis of the control of C3b by the complement regulatory proteins factors H and I.''; PubMed Europe PMC Scholia
- Medof ME, Kinoshita T, Nussenzweig V.; ''Inhibition of complement activation on the surface of cells after incorporation of decay-accelerating factor (DAF) into their membranes.''; PubMed Europe PMC Scholia
- Goicoechea de Jorge E, Caesar JJ, Malik TH, Patel M, Colledge M, Johnson S, Hakobyan S, Morgan BP, Harris CL, Pickering MC, Lea SM.; ''Dimerization of complement factor H-related proteins modulates complement activation in vivo.''; PubMed Europe PMC Scholia
- Degen SJ, Davie EW.; ''Nucleotide sequence of the gene for human prothrombin.''; PubMed Europe PMC Scholia
- Forneris F, Ricklin D, Wu J, Tzekou A, Wallace RS, Lambris JD, Gros P.; ''Structures of C3b in complex with factors B and D give insight into complement convertase formation.''; PubMed Europe PMC Scholia
- Smith CA, Pangburn MK, Vogel CW, Müller-Eberhard HJ.; ''Molecular architecture of human properdin, a positive regulator of the alternative pathway of complement.''; PubMed Europe PMC Scholia
- Gout E, Garlatti V, Smith DF, Lacroix M, Dumestre-Pérard C, Lunardi T, Martin L, Cesbron JY, Arlaud GJ, Gaboriaud C, Thielens NM.; ''Carbohydrate recognition properties of human ficolins: glycan array screening reveals the sialic acid binding specificity of M-ficolin.''; PubMed Europe PMC Scholia
- Honoré C, Rørvig S, Munthe-Fog L, Hummelshøj T, Madsen HO, Borregaard N, Garred P.; ''The innate pattern recognition molecule Ficolin-1 is secreted by monocytes/macrophages and is circulating in human plasma.''; PubMed Europe PMC Scholia
- Christmas SE, Christmas SE, de la Mata Espinosa CT, Halliday D, Buxton CA, Cummerson JA, Johnson PM.; ''Levels of expression of complement regulatory proteins CD46, CD55 and CD59 on resting and activated human peripheral blood leucocytes.''; PubMed Europe PMC Scholia
- Sim RB, Laich A.; ''Serine proteases of the complement system.''; PubMed Europe PMC Scholia
- Ames RS, Li Y, Sarau HM, Nuthulaganti P, Foley JJ, Ellis C, Zeng Z, Su K, Jurewicz AJ, Hertzberg RP, Bergsma DJ, Kumar C.; ''Molecular cloning and characterization of the human anaphylatoxin C3a receptor.''; PubMed Europe PMC Scholia
- Dodds AW, Ren XD, Willis AC, Law SK.; ''The reaction mechanism of the internal thioester in the human complement component C4.''; PubMed Europe PMC Scholia
- Arlaud GJ, Reboul A, Sim RB, Colomb MG.; ''Interaction of C1-inhibitor with the C1r and C1s subcomponents in human C1.''; PubMed Europe PMC Scholia
History
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External references
DataNodes
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Name | Type | Database reference | Comment |
---|---|---|---|
1,3-beta-D-glucan [plasma membrane] | Metabolite | CHEBI:37671 (ChEBI) | |
11xCbxE-PROS1
[extracellular region] | Protein | P07225 (Uniprot-TrEMBL) | |
11xCbxE-PROS1 | Protein | P07225 (Uniprot-TrEMBL) | |
Antigen: antibody:
C1 (activated C1R and C1S) complex | Complex | REACT_8066 (Reactome) | |
Antigen: antibody:
C1 (activated C1R) complex | Complex | REACT_8973 (Reactome) | |
Antigen: antibody: C1 complex | Complex | REACT_8034 (Reactome) | |
Bacterial
mannose-based carbohydrate surface pattern | REACT_8923 (Reactome) | ||
C-reactive protein pentamer:phosphocholine:C1Q | Complex | REACT_25403 (Reactome) | |
C1QA [extracellular region] | Protein | P02745 (Uniprot-TrEMBL) | |
C1QB(26-251)
[extracellular region] | Protein | P02746 (Uniprot-TrEMBL) | |
C1QC [extracellular region] | Protein | P02747 (Uniprot-TrEMBL) | |
C1R C-terminal
fragment [extracellular region] | Protein | P00736 (Uniprot-TrEMBL) | |
C1R N-terminal
fragment [extracellular region] | Protein | P00736 (Uniprot-TrEMBL) | |
C1R(18-705)
[extracellular region] | Protein | P00736 (Uniprot-TrEMBL) | |
C1S C-terminal
fragment [extracellular region] | Protein | P09871 (Uniprot-TrEMBL) | |
C1S N-terminal
fragment [extracellular region] | Protein | P09871 (Uniprot-TrEMBL) | |
C1S(16-688)
[extracellular region] | Protein | P09871 (Uniprot-TrEMBL) | |
C2 | Protein | P06681 (Uniprot-TrEMBL) | |
C2a [extracellular region] | Protein | P06681 (Uniprot-TrEMBL) | |
C2a | Protein | P06681 (Uniprot-TrEMBL) | |
C2b | Protein | P06681 (Uniprot-TrEMBL) | |
C3 alpha chain
[extracellular region] | Protein | P01024 (Uniprot-TrEMBL) | |
C3 beta chain
[extracellular region] | Protein | P01024 (Uniprot-TrEMBL) | |
C3 beta chain [plasma membrane] | Protein | P01024 (Uniprot-TrEMBL) | |
C3 convertases | REACT_8751 (Reactome) | ||
C3(H2O):Factor B | Complex | REACT_8649 (Reactome) | |
C3(H2O):Factor Bb | Complex | REACT_8857 (Reactome) | |
C3(H2O) | Complex | REACT_8268 (Reactome) | |
C3a | Protein | P01024 (Uniprot-TrEMBL) | |
C3b alpha'
[extracellular region] | Protein | P01024 (Uniprot-TrEMBL) | |
C3b:Factor
Bb:C3b:Properdin complex | Complex | REACT_8784 (Reactome) | |
C3b | Complex | REACT_8621 (Reactome) | Linked by disulphide bond between positions 559 and 816. |
C3c alpha' chain
fragment 1 [extracellular region] | Protein | P01024 (Uniprot-TrEMBL) | |
C3c alpha' chain
fragment 1 precursor [extracellular region] | Protein | P01024 (Uniprot-TrEMBL) | |
C3c alpha' chain
fragment 1 precursor [plasma membrane] | Protein | P01024 (Uniprot-TrEMBL) | |
C3c alpha' chain
fragment 2 [extracellular region] | Protein | P01024 (Uniprot-TrEMBL) | |
C3c alpha' chain
fragment 2 [plasma membrane] | Protein | P01024 (Uniprot-TrEMBL) | |
C3c | Complex | REACT_164188 (Reactome) | |
C3dg | Protein | P01024 (Uniprot-TrEMBL) | |
C3f [extracellular region] | Protein | P01024 (Uniprot-TrEMBL) | |
C3f | Protein | P01024 (Uniprot-TrEMBL) | |
C4 activator | REACT_8154 (Reactome) | ||
C4 alpha
[extracellular region] | Protein | P0C0L4 (Uniprot-TrEMBL) | C4 alpha chain has a thioester bond between Cys 1010 and Gln 1013 |
C4 binding protein:C4bC2a | Complex | REACT_120190 (Reactome) | |
C4 binding protein:protein S | Complex | REACT_119894 (Reactome) | |
C4-binding protein:C4b | Complex | REACT_118966 (Reactome) | |
C4A alpha b
[extracellular region] | Protein | P0C0L4 (Uniprot-TrEMBL) | C4 alpha chain has a thioester bond between Cys 1010 and Gln 1013 |
C4A alpha3
[extracellular region] | Protein | P0C0L4 (Uniprot-TrEMBL) | |
C4A alpha4 fragment
[extracellular region] | Protein | P0C0L4 (Uniprot-TrEMBL) | |
C4A beta
[extracellular region] | Protein | P0C0L4 (Uniprot-TrEMBL) | |
C4A gamma
[extracellular region] | Protein | P0C0L4 (Uniprot-TrEMBL) | |
C4B alpha
[extracellular region] | Protein | P0C0L5 (Uniprot-TrEMBL) | |
C4B alpha chain
fragment b [extracellular region] | Protein | P0C0L5 (Uniprot-TrEMBL) | |
C4B alpha3
[extracellular region] | Protein | P0C0L5 (Uniprot-TrEMBL) | |
C4B alpha4 fragment
[extracellular region] | Protein | P0C0L5 (Uniprot-TrEMBL) | |
C4B beta
[extracellular region] | Protein | P0C0L5 (Uniprot-TrEMBL) | |
C4B gamma
[extracellular region] | Protein | P0C0L5 (Uniprot-TrEMBL) | |
C4BPA [plasma membrane] | Protein | P04003 (Uniprot-TrEMBL) | |
C4BPB [plasma membrane] | Protein | P20851 (Uniprot-TrEMBL) | |
C4a | Protein | REACT_25991 (Reactome) | |
C4b with hydrolysed thioester | Complex | REACT_164040 (Reactome) | |
C4b, C3b | Complex | REACT_119260 (Reactome) | |
C4b-binding protein:Factor I | Complex | REACT_119445 (Reactome) | |
C4b-binding protein | Complex | REACT_120080 (Reactome) | |
C4b:C2a:C3b | Complex | REACT_8556 (Reactome) | |
C4bC2a, C3bBb | Complex | REACT_119171 (Reactome) | |
C4c, C3f | Complex | REACT_119917 (Reactome) | |
C4c | Complex | REACT_119729 (Reactome) | |
C4d, iC3b | Protein | REACT_119732 (Reactome) | |
C4d | Protein | REACT_119059 (Reactome) | |
C5 alpha
[extracellular region] | Protein | P01031 (Uniprot-TrEMBL) | |
C5 beta
[extracellular region] | Protein | P01031 (Uniprot-TrEMBL) | |
C5 convertases | REACT_8864 (Reactome) | ||
C5a | Protein | P01031 (Uniprot-TrEMBL) | |
C5b alpha'
[extracellular region] | Protein | P01031 (Uniprot-TrEMBL) | |
C5b:C6 complex | Complex | REACT_8500 (Reactome) | |
C5b:C6:C7 complex | Complex | REACT_8333 (Reactome) | |
C5b:C6:C7 complex | Complex | REACT_8454 (Reactome) | |
C5b:C6:C7:C8 complex | Complex | REACT_8352 (Reactome) | |
C5b | Complex | REACT_8814 (Reactome) | Linked by disulphide bond between positions 559 and 816. |
C6 [extracellular region] | Protein | P13671 (Uniprot-TrEMBL) | |
C6 | Protein | P13671 (Uniprot-TrEMBL) | |
C7(22-843)
[extracellular region] | Protein | P10643 (Uniprot-TrEMBL) | |
C7(22-843) | Protein | P10643 (Uniprot-TrEMBL) | |
C8A [extracellular region] | Protein | P07357 (Uniprot-TrEMBL) | |
C8B [extracellular region] | Protein | P07358 (Uniprot-TrEMBL) | |
C8G [extracellular region] | Protein | P07360 (Uniprot-TrEMBL) | |
C8 | Complex | REACT_8563 (Reactome) | |
C9(22-559)
[extracellular region] | Protein | P02748 (Uniprot-TrEMBL) | |
C9(22-559) | Protein | P02748 (Uniprot-TrEMBL) | |
CD46 [plasma membrane] | Protein | P15529 (Uniprot-TrEMBL) | |
CD46 | Protein | P15529 (Uniprot-TrEMBL) | |
CD55 [plasma membrane] | Protein | P08174 (Uniprot-TrEMBL) | |
CD55 | Protein | P08174 (Uniprot-TrEMBL) | |
CD59 [plasma membrane] | Protein | P13987 (Uniprot-TrEMBL) | |
CD59:C5b-C9 | Complex | REACT_164087 (Reactome) | |
CD59 | Protein | P13987 (Uniprot-TrEMBL) | |
CFB(26-259) | Protein | P00751 (Uniprot-TrEMBL) | |
CFB(26-764)
[extracellular region] | Protein | P00751 (Uniprot-TrEMBL) | |
CFB(26-764) | Protein | P00751 (Uniprot-TrEMBL) | |
CFB(260-764)
[extracellular region] | Protein | P00751 (Uniprot-TrEMBL) | |
CFB(260-764) [plasma membrane] | Protein | P00751 (Uniprot-TrEMBL) | |
CFB(260-764) | Protein | P00751 (Uniprot-TrEMBL) | |
CFD | Protein | P00746 (Uniprot-TrEMBL) | |
CFH [extracellular region] | Protein | P08603 (Uniprot-TrEMBL) | |
CFH | Protein | P08603 (Uniprot-TrEMBL) | |
CFI(19-335)
[extracellular region] | Protein | P05156 (Uniprot-TrEMBL) | |
CFI(19-335) | Protein | P05156 (Uniprot-TrEMBL) | |
CFI(340-583)
[extracellular region] | Protein | P05156 (Uniprot-TrEMBL) | |
CFI(340-583) | Protein | P05156 (Uniprot-TrEMBL) | |
CR1 [plasma membrane] | Protein | P17927 (Uniprot-TrEMBL) | |
CR1:C3bBb, C4bC2a complexes | Complex | REACT_120030 (Reactome) | |
CR1:C3b | Complex | REACT_119014 (Reactome) | |
CR1:C4b | Complex | REACT_119535 (Reactome) | |
CR1:iC3b | Complex | REACT_164751 (Reactome) | |
CR1 | Protein | P17927 (Uniprot-TrEMBL) | |
CRP(19-224)
[extracellular region] | Protein | P02741 (Uniprot-TrEMBL) | |
Ca2+ [extracellular region] | Metabolite | CHEBI:29108 (ChEBI) | |
Ca2+ | Metabolite | CHEBI:29108 (ChEBI) | |
Cell
surface:C3b:Factor Bb:Properdin | Complex | REACT_8531 (Reactome) | |
Cell
surface:C3b:Factor Bb | Complex | REACT_8668 (Reactome) | |
Cell
surface:C3b:Factor B complex | Complex | REACT_8205 (Reactome) | |
Cell surface:FH,FHR3:C3bBb | Complex | REACT_118983 (Reactome) | |
Cell surface:FH,FHR3:C3b | Complex | REACT_119386 (Reactome) | |
Cell surface:C3b | Complex | REACT_26114 (Reactome) | |
Cell surface:C4b:C2a | Complex | REACT_8917 (Reactome) | |
Cell surface:C4b | Complex | REACT_25739 (Reactome) | |
Cell surface | REACT_26575 (Reactome) | This entity is intended to represent any molecule that might be at the outer cell surface of any cell, host or microbial. | |
Complement Factor 4 | Complex | REACT_26761 (Reactome) | |
Complement factor
I:Cell surface:FH,FHR3:C3b | Complex | REACT_119579 (Reactome) | |
Complement factor I:Factor H:C3b | Complex | REACT_119450 (Reactome) | |
Complement factor 3 | Complex | REACT_8213 (Reactome) | Linked by disulphide bond between positions 559 and 816. |
Complement factor 5 | Complex | REACT_8215 (Reactome) | |
Complement factor D | Protein | REACT_161511 (Reactome) | This CandidateSet contains sequences identified by William Pearson's analysis of Reactome catalyst entities. Catalyst entity sequences were used to identify analagous sequences that shared overall homology and active site homology. Sequences in this Candidate set were identified in an April 24, 2012 analysis. |
Complement factor I | Complex | REACT_119465 (Reactome) | |
D-fucose [plasma membrane] | Metabolite | CHEBI:28847 (ChEBI) | |
DAF:C3 convertase complexes | Complex | REACT_119393 (Reactome) | |
DAF:C3b | Complex | REACT_119929 (Reactome) | |
DAF:C4b | Complex | REACT_119228 (Reactome) | |
FCN1 [extracellular region] | Protein | O00602 (Uniprot-TrEMBL) | |
FCN1 ligand | Metabolite | REACT_165133 (Reactome) | |
FCN1:MASP2 dimer:MASP1 dimer | Complex | REACT_164741 (Reactome) | |
FCN1:MASPs:Ca2+:FCN1 ligand | Complex | REACT_165421 (Reactome) | |
FCN2 [extracellular region] | Protein | Q15485 (Uniprot-TrEMBL) | |
FCN2 ligand | Metabolite | REACT_164334 (Reactome) | |
FCN2:MASP2 dimer:MASP1 dimer | Complex | REACT_165253 (Reactome) | |
FCN2:MASPs:Ca2+:FCN2 ligand | Complex | REACT_164948 (Reactome) | |
FCN3 [extracellular region] | Protein | O75636 (Uniprot-TrEMBL) | |
FCN3 ligand | Metabolite | REACT_165296 (Reactome) | |
FCN3:MASP2 dimer:MASP1 dimer | Complex | REACT_165152 (Reactome) | |
FCN3:MASPs:Ca2+:FCN3 ligand | Complex | REACT_164302 (Reactome) | |
FH, FHR-3 | Protein | REACT_119141 (Reactome) | |
Factor H:C3b | Complex | REACT_120113 (Reactome) | |
Factor H:Host cell surface | Complex | REACT_119254 (Reactome) | |
Factor I:MCP,
CR1:C4b, C3b complexes | Complex | REACT_120091 (Reactome) | |
H2O | Metabolite | CHEBI:15377 (ChEBI) | |
Heparins [plasma membrane] | Metabolite | CHEBI:24505 (ChEBI) | |
Host cell surface | Complex | REACT_119096 (Reactome) | |
IGHG1(1-330)
[extracellular region] | Protein | P01857 (Uniprot-TrEMBL) | |
IGHG2(1-326)
[extracellular region] | Protein | P01859 (Uniprot-TrEMBL) | |
IGHG3 [extracellular region] | Protein | P01860 (Uniprot-TrEMBL) | |
IGHG4(1-327)
[extracellular region] | Protein | P01861 (Uniprot-TrEMBL) | |
IGHV(1-?)
[extracellular region] | Protein | A2KUC3 (Uniprot-TrEMBL) | |
IGHV7-81(1-?)
[extracellular region] | Protein | Q6PIL0 (Uniprot-TrEMBL) | |
IGKC(1-106)
[extracellular region] | Protein | P01834 (Uniprot-TrEMBL) | |
IGKV1-5(23-?)
[extracellular region] | Protein | P01602 (Uniprot-TrEMBL) | |
IGKV4-1(21-?)
[extracellular region] | Protein | P06312 (Uniprot-TrEMBL) | |
IGKVA18(21-?)
[extracellular region] | Protein | A2NJV5 (Uniprot-TrEMBL) | |
IGLC1(1-105)
[extracellular region] | Protein | P0CG04 (Uniprot-TrEMBL) | |
IGLC2(?-106)
[extracellular region] | Protein | P0CG05 (Uniprot-TrEMBL) | |
IGLC3(?-106)
[extracellular region] | Protein | P0CG06 (Uniprot-TrEMBL) | |
IGLC6(?-106)
[extracellular region] | Protein | P0CF74 (Uniprot-TrEMBL) | |
IGLC7(?-106)
[extracellular region] | Protein | A0M8Q6 (Uniprot-TrEMBL) | |
IGLV(23-?)
[extracellular region] | Protein | A2NXD2 (Uniprot-TrEMBL) | |
IGLV1-36(1-?)
[extracellular region] | Protein | Q5NV67 (Uniprot-TrEMBL) | |
IGLV1-40(1-?)
[extracellular region] | Protein | Q5NV69 (Uniprot-TrEMBL) | |
IGLV1-44(1-?)
[extracellular region] | Protein | Q5NV81 (Uniprot-TrEMBL) | |
IGLV10-54(1-?)
[extracellular region] | Protein | Q5NV86 (Uniprot-TrEMBL) | |
IGLV11-55(1-?)
[extracellular region] | Protein | Q5NV87 (Uniprot-TrEMBL) | |
IGLV2-11(1-?)
[extracellular region] | Protein | Q5NV84 (Uniprot-TrEMBL) | |
IGLV2-18(1-?)
[extracellular region] | Protein | Q5NV65 (Uniprot-TrEMBL) | |
IGLV2-23(1-?)
[extracellular region] | Protein | Q5NV89 (Uniprot-TrEMBL) | |
IGLV2-33(1-?)
[extracellular region] | Protein | Q5NV66 (Uniprot-TrEMBL) | |
IGLV3-12(1-?)
[extracellular region] | Protein | Q5NV85 (Uniprot-TrEMBL) | |
IGLV3-16(1-?)
[extracellular region] | Protein | Q5NV64 (Uniprot-TrEMBL) | |
IGLV3-22(1-?)
[extracellular region] | Protein | Q5NV75 (Uniprot-TrEMBL) | |
IGLV3-25(1-?)
[extracellular region] | Protein | Q5NV90 (Uniprot-TrEMBL) | |
IGLV3-27(1-?)
[extracellular region] | Protein | Q5NV91 (Uniprot-TrEMBL) | |
IGLV4-3(1-?)
[extracellular region] | Protein | Q5NV61 (Uniprot-TrEMBL) | |
IGLV4-60(1-?)
[extracellular region] | Protein | Q5NV79 (Uniprot-TrEMBL) | |
IGLV4-69(1-?)
[extracellular region] | Protein | Q5NV92 (Uniprot-TrEMBL) | |
IGLV5-37(1-?)
[extracellular region] | Protein | Q5NV68 (Uniprot-TrEMBL) | |
IGLV5-45(1-?)
[extracellular region] | Protein | Q5NV82 (Uniprot-TrEMBL) | |
IGLV7-43(1-?)
[extracellular region] | Protein | Q5NV80 (Uniprot-TrEMBL) | |
IGLV7-46(1-?)
[extracellular region] | Protein | Q5NV83 (Uniprot-TrEMBL) | |
IGLV8-61(1-?)
[extracellular region] | Protein | Q5NV62 (Uniprot-TrEMBL) | |
Ig heavy chain V-I
region EU [extracellular region] | Protein | P01742 (Uniprot-TrEMBL) | |
Ig heavy chain V-I
region HG3 [extracellular region] | Protein | P01743 (Uniprot-TrEMBL) | |
Ig heavy chain V-I
region Mot [extracellular region] | Protein | P06326 (Uniprot-TrEMBL) | |
Ig heavy chain V-I
region ND [extracellular region] | Protein | P01744 (Uniprot-TrEMBL) | |
Ig heavy chain V-I
region SIE [extracellular region] | Protein | P01761 (Uniprot-TrEMBL) | |
Ig heavy chain V-I
region WOL [extracellular region] | Protein | P01760 (Uniprot-TrEMBL) | |
Ig heavy chain V-II
region ARH-77 [extracellular region] | Protein | P06331 (Uniprot-TrEMBL) | |
Ig heavy chain V-II
region COR [extracellular region] | Protein | P01815 (Uniprot-TrEMBL) | |
Ig heavy chain V-II
region DAW [extracellular region] | Protein | P01816 (Uniprot-TrEMBL) | |
Ig heavy chain V-II
region HE [extracellular region] | Protein | P01818 (Uniprot-TrEMBL) | |
Ig heavy chain V-II
region MCE [extracellular region] | Protein | P01817 (Uniprot-TrEMBL) | |
Ig heavy chain V-II
region NEWM [extracellular region] | Protein | P01825 (Uniprot-TrEMBL) | |
Ig heavy chain V-II
region OU [extracellular region] | Protein | P01814 (Uniprot-TrEMBL) | |
Ig heavy chain V-II
region SESS [extracellular region] | Protein | P04438 (Uniprot-TrEMBL) | |
Ig heavy chain V-II
region WAH [extracellular region] | Protein | P01824 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region BRO [extracellular region] | Protein | P01766 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region BUR [extracellular region] | Protein | P01773 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region BUT [extracellular region] | Protein | P01767 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region CAM [extracellular region] | Protein | P01768 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region DOB [extracellular region] | Protein | P01782 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region GA [extracellular region] | Protein | P01769 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region GAL [extracellular region] | Protein | P01781 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region HIL [extracellular region] | Protein | P01771 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region JON [extracellular region] | Protein | P01780 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region KOL [extracellular region] | Protein | P01772 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region LAY [extracellular region] | Protein | P01775 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region NIE [extracellular region] | Protein | P01770 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region POM [extracellular region] | Protein | P01774 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region TEI [extracellular region] | Protein | P01777 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region TIL [extracellular region] | Protein | P01765 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region TRO [extracellular region] | Protein | P01762 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region TUR [extracellular region] | Protein | P01779 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region WAS [extracellular region] | Protein | P01776 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region WEA [extracellular region] | Protein | P01763 (Uniprot-TrEMBL) | |
Ig heavy chain V-III
region ZAP [extracellular region] | Protein | P01778 (Uniprot-TrEMBL) | |
Ig kappa chain V
region EV15 [extracellular region] | Protein | P06315 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region AG [extracellular region] | Protein | P01593 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region AU [extracellular region] | Protein | P01594 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region BAN [extracellular region] | Protein | P04430 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region Bi [extracellular region] | Protein | P01595 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region CAR [extracellular region] | Protein | P01596 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region DEE [extracellular region] | Protein | P01597 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region Daudi [extracellular region] | Protein | P04432 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region EU [extracellular region] | Protein | P01598 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region Gal [extracellular region] | Protein | P01599 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region HK101 [extracellular region] | Protein | P01601 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region Hau [extracellular region] | Protein | P01600 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region Ka [extracellular region] | Protein | P01603 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region Kue [extracellular region] | Protein | P01604 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region Lay [extracellular region] | Protein | P01605 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region Mev [extracellular region] | Protein | P01612 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region Ni [extracellular region] | Protein | P01613 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region OU [extracellular region] | Protein | P01606 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region Rei [extracellular region] | Protein | P01607 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region Roy [extracellular region] | Protein | P01608 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region Scw [extracellular region] | Protein | P01609 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region WAT [extracellular region] | Protein | P80362 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region WEA [extracellular region] | Protein | P01610 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region Walker [extracellular region] | Protein | P04431 (Uniprot-TrEMBL) | |
Ig kappa chain V-I
region Wes [extracellular region] | Protein | P01611 (Uniprot-TrEMBL) | |
Ig kappa chain V-II
region Cum [extracellular region] | Protein | P01614 (Uniprot-TrEMBL) | |
Ig kappa chain V-II
region FR [extracellular region] | Protein | P01615 (Uniprot-TrEMBL) | |
Ig kappa chain V-II
region GM607 [extracellular region] | Protein | P06309 (Uniprot-TrEMBL) | |
Ig kappa chain V-II
region MIL [extracellular region] | Protein | P01616 (Uniprot-TrEMBL) | |
Ig kappa chain V-II
region RPMI 6410 [extracellular region] | Protein | P06310 (Uniprot-TrEMBL) | |
Ig kappa chain V-II
region TEW [extracellular region] | Protein | P01617 (Uniprot-TrEMBL) | |
Ig kappa chain V-III
region B6 [extracellular region] | Protein | P01619 (Uniprot-TrEMBL) | |
Ig kappa chain V-III
region CLL [extracellular region] | Protein | P04207 (Uniprot-TrEMBL) | |
Ig kappa chain V-III
region GOL [extracellular region] | Protein | P04206 (Uniprot-TrEMBL) | |
Ig kappa chain V-III
region HAH [extracellular region] | Protein | P18135 (Uniprot-TrEMBL) | |
Ig kappa chain V-III
region HIC [extracellular region] | Protein | P18136 (Uniprot-TrEMBL) | |
Ig kappa chain V-III
region IARC/BL41 [extracellular region] | Protein | P06311 (Uniprot-TrEMBL) | |
Ig kappa chain V-III
region NG9 [extracellular region] | Protein | P01621 (Uniprot-TrEMBL) | |
Ig kappa chain V-III
region POM [extracellular region] | Protein | P01624 (Uniprot-TrEMBL) | |
Ig kappa chain V-III
region SIE [extracellular region] | Protein | P01620 (Uniprot-TrEMBL) | |
Ig kappa chain V-III
region Ti [extracellular region] | Protein | P01622 (Uniprot-TrEMBL) | |
Ig kappa chain V-III
region VG [extracellular region] | Protein | P04433 (Uniprot-TrEMBL) | |
Ig kappa chain V-III
region VH [extracellular region] | Protein | P04434 (Uniprot-TrEMBL) | |
Ig kappa chain V-III
region WOL [extracellular region] | Protein | P01623 (Uniprot-TrEMBL) | |
Ig kappa chain V-IV
region B17 [extracellular region] | Protein | P06314 (Uniprot-TrEMBL) | |
Ig kappa chain V-IV
region JI [extracellular region] | Protein | P06313 (Uniprot-TrEMBL) | |
Ig kappa chain V-IV
region Len [extracellular region] | Protein | P01625 (Uniprot-TrEMBL) | |
Ig kappa chain V-IV
region STH [extracellular region] | Protein | P83593 (Uniprot-TrEMBL) | |
Ig lambda chain
V-III region LOI [extracellular region] | Protein | P80748 (Uniprot-TrEMBL) | |
Ig lambda chain
V-III region SH [extracellular region] | Protein | P01714 (Uniprot-TrEMBL) | |
Ig lambda chain
V-VII region MOT [extracellular region] | Protein | P01720 (Uniprot-TrEMBL) | |
Ig lambda chain V
region 4A [extracellular region] | Protein | P04211 (Uniprot-TrEMBL) | |
Ig lambda chain V-I
region BL2 [extracellular region] | Protein | P06316 (Uniprot-TrEMBL) | |
Ig lambda chain V-I
region EPS [extracellular region] | Protein | P06888 (Uniprot-TrEMBL) | |
Ig lambda chain V-I
region HA [extracellular region] | Protein | P01700 (Uniprot-TrEMBL) | |
Ig lambda chain V-I
region MEM [extracellular region] | Protein | P06887 (Uniprot-TrEMBL) | |
Ig lambda chain V-I
region NEW [extracellular region] | Protein | P01701 (Uniprot-TrEMBL) | |
Ig lambda chain V-I
region NEWM [extracellular region] | Protein | P01703 (Uniprot-TrEMBL) | |
Ig lambda chain V-I
region NIG-64 [extracellular region] | Protein | P01702 (Uniprot-TrEMBL) | |
Ig lambda chain V-I
region VOR [extracellular region] | Protein | P01699 (Uniprot-TrEMBL) | |
Ig lambda chain V-I
region WAH [extracellular region] | Protein | P04208 (Uniprot-TrEMBL) | |
Ig lambda chain V-II
region BO [extracellular region] | Protein | P01710 (Uniprot-TrEMBL) | |
Ig lambda chain V-II
region BOH [extracellular region] | Protein | P01706 (Uniprot-TrEMBL) | |
Ig lambda chain V-II
region BUR [extracellular region] | Protein | P01708 (Uniprot-TrEMBL) | |
Ig lambda chain V-II
region MGC [extracellular region] | Protein | P01709 (Uniprot-TrEMBL) | |
Ig lambda chain V-II
region NEI [extracellular region] | Protein | P01705 (Uniprot-TrEMBL) | |
Ig lambda chain V-II
region NIG-58 [extracellular region] | Protein | P01713 (Uniprot-TrEMBL) | |
Ig lambda chain V-II
region NIG-84 [extracellular region] | Protein | P04209 (Uniprot-TrEMBL) | |
Ig lambda chain V-II
region TOG [extracellular region] | Protein | P01704 (Uniprot-TrEMBL) | |
Ig lambda chain V-II
region TRO [extracellular region] | Protein | P01707 (Uniprot-TrEMBL) | |
Ig lambda chain V-II
region VIL [extracellular region] | Protein | P01711 (Uniprot-TrEMBL) | |
Ig lambda chain V-II
region WIN [extracellular region] | Protein | P01712 (Uniprot-TrEMBL) | |
Ig lambda chain V-IV
region Bau [extracellular region] | Protein | P01715 (Uniprot-TrEMBL) | |
Ig lambda chain V-IV
region Hil [extracellular region] | Protein | P01717 (Uniprot-TrEMBL) | |
Ig lambda chain V-IV
region Kern [extracellular region] | Protein | P01718 (Uniprot-TrEMBL) | |
Ig lambda chain V-IV
region MOL [extracellular region] | Protein | P06889 (Uniprot-TrEMBL) | |
Ig lambda chain V-IV
region X [extracellular region] | Protein | P01716 (Uniprot-TrEMBL) | |
Ig lambda chain V-V
region DEL [extracellular region] | Protein | P01719 (Uniprot-TrEMBL) | |
Ig lambda chain V-VI
region AR [extracellular region] | Protein | P01721 (Uniprot-TrEMBL) | |
Ig lambda chain V-VI
region EB4 [extracellular region] | Protein | P06319 (Uniprot-TrEMBL) | |
Ig lambda chain V-VI
region NIG-48 [extracellular region] | Protein | P01722 (Uniprot-TrEMBL) | |
Ig lambda chain V-VI
region SUT [extracellular region] | Protein | P06317 (Uniprot-TrEMBL) | |
Ig lambda chain V-VI
region WLT [extracellular region] | Protein | P06318 (Uniprot-TrEMBL) | |
IgH heavy chain
V-III region VH26 precursor [extracellular region] | Protein | P01764 (Uniprot-TrEMBL) | |
Lipoteichoic acid [plasma membrane] | Metabolite | CHEBI:28640 (ChEBI) | |
MASP1(20-448)
[extracellular region] | Protein | P48740 (Uniprot-TrEMBL) | |
MASP1(20-699)
[extracellular region] | Protein | P48740 (Uniprot-TrEMBL) | |
MASP1(449-699)
[extracellular region] | Protein | P48740 (Uniprot-TrEMBL) | |
MASP2-1
[extracellular region] | Protein | O00187-1 (Uniprot-TrEMBL) | |
MASP2-1(16-444)
[extracellular region] | Protein | O00187-1 (Uniprot-TrEMBL) | |
MASP2-1(445-686)
[extracellular region] | Protein | O00187-1 (Uniprot-TrEMBL) | |
MBL bound to
mannose-based carbohydrates on bacterial surfaces | Complex | REACT_8711 (Reactome) | |
MBL-II:MASP-2
dimer:MASP-1 dimer complex | Complex | REACT_8380 (Reactome) | |
MBL/FCN:activated
MASP:carbohydrate patterns | Complex | REACT_165602 (Reactome) | |
MBL/Ficolin:MASPs
bound to carbohydrate patterns | Complex | REACT_165125 (Reactome) | |
MBL2 [extracellular region] | Protein | P11226 (Uniprot-TrEMBL) | |
MBL:activated
MASPs:mannose-based carbohydrates | Complex | REACT_8515 (Reactome) | |
MCP, CR1:C4b:C3b complexes | Complex | REACT_120251 (Reactome) | |
MCP, CR1 | Protein | REACT_119720 (Reactome) | CR1 and MCP are widely distributed cell surface molecules that bind C4b and C3b, and act as cofactors for Complement factor I, thereby regulating the classical and alternative C3 convertases. |
MCP:C3b | Complex | REACT_119903 (Reactome) | |
MCP:C4b | Complex | REACT_119237 (Reactome) | |
Membrane Attack Complex | Complex | REACT_8325 (Reactome) | |
N-acetyl-D-glucosamine [plasma membrane] | Metabolite | CHEBI:28009 (ChEBI) | |
N-acetylgalactosamine [plasma membrane] | Metabolite | CHEBI:40356 (ChEBI) | |
PCho [plasma membrane] | Metabolite | CHEBI:36700 (ChEBI) | |
Properdin oligomer | REACT_8730 (Reactome) | ||
Sialic acid [plasma membrane] | Metabolite | CHEBI:28879 (ChEBI) | |
VTN(20-?)
[extracellular region] | Protein | P04004 (Uniprot-TrEMBL) | |
VTN(20-?) | Protein | P04004 (Uniprot-TrEMBL) | |
VTN:C5b:C6:C7:C8:C9 | Complex | REACT_164606 (Reactome) | |
VTN:C5b:C6:C7 | Complex | REACT_165289 (Reactome) | |
dNQ-C3(672-1663)
[extracellular region] | Protein | P01024 (Uniprot-TrEMBL) | |
dNQ-C4A(757-1446)
[extracellular region] | Protein | P0C0L4 (Uniprot-TrEMBL) | |
dNQ-C4B(757-1446)
[extracellular region] | Protein | P0C0L5 (Uniprot-TrEMBL) | |
iC3b | Complex | REACT_119218 (Reactome) | |
iC3b | Complex | REACT_120169 (Reactome) | |
thioester-C1010-Q1013-C4b | Complex | REACT_26471 (Reactome) |
Annotated Interactions
View all... |
Source | Target | Type | Database reference | Comment |
---|---|---|---|---|
11xCbxE-PROS1 | REACT_118836 (Reactome) | |||
Antigen: antibody:
C1 (activated C1R and C1S) complex | Arrow | REACT_7977 (Reactome) | ||
Antigen: antibody:
C1 (activated C1R) complex | Arrow | REACT_7978 (Reactome) | ||
Antigen: antibody:
C1 (activated C1R) complex | REACT_7977 (Reactome) | |||
Antigen: antibody:
C1 (activated C1R) complex | mim-catalysis | REACT_7977 (Reactome) | ||
Antigen: antibody: C1 complex | REACT_7978 (Reactome) | |||
Antigen: antibody: C1 complex | mim-catalysis | REACT_7978 (Reactome) | ||
Bacterial
mannose-based carbohydrate surface pattern | REACT_7983 (Reactome) | |||
C-reactive protein pentamer:phosphocholine:C1Q | Arrow | REACT_7978 (Reactome) | ||
C2 | REACT_7959 (Reactome) | |||
C2a | Arrow | REACT_118584 (Reactome) | ||
C2a | Arrow | REACT_118641 (Reactome) | ||
C2a | Arrow | REACT_118692 (Reactome) | ||
C2a | Arrow | REACT_118738 (Reactome) | ||
C2a | Arrow | REACT_7959 (Reactome) | ||
C2a | REACT_8014 (Reactome) | |||
C2b | Arrow | REACT_7959 (Reactome) | ||
C3 convertases | REACT_118641 (Reactome) | |||
C3 convertases | mim-catalysis | REACT_7990 (Reactome) | ||
C3(H2O):Factor B | Arrow | REACT_8013 (Reactome) | ||
C3(H2O):Factor B | REACT_7981 (Reactome) | |||
C3(H2O):Factor Bb | Arrow | REACT_7981 (Reactome) | ||
C3(H2O):Factor Bb | mim-catalysis | REACT_7948 (Reactome) | ||
C3(H2O) | Arrow | REACT_118641 (Reactome) | ||
C3(H2O) | Arrow | REACT_8007 (Reactome) | ||
C3(H2O) | REACT_8013 (Reactome) | |||
C3a | Arrow | REACT_7948 (Reactome) | ||
C3a | Arrow | REACT_7986 (Reactome) | ||
C3a | Arrow | REACT_7990 (Reactome) | ||
C3b:Factor
Bb:C3b:Properdin complex | Arrow | REACT_7986 (Reactome) | ||
C3b | Arrow | REACT_118641 (Reactome) | ||
C3b | Arrow | REACT_7948 (Reactome) | ||
C3b | Arrow | REACT_7990 (Reactome) | ||
C3b | REACT_118712 (Reactome) | |||
C3b | REACT_25075 (Reactome) | |||
C3c | Arrow | REACT_163860 (Reactome) | ||
C3dg | Arrow | REACT_163860 (Reactome) | ||
C3f | Arrow | REACT_118650 (Reactome) | ||
C3f | Arrow | REACT_118841 (Reactome) | ||
C4 activator | mim-catalysis | REACT_7959 (Reactome) | ||
C4 activator | mim-catalysis | REACT_8002 (Reactome) | ||
C4 binding protein:C4bC2a | Arrow | REACT_118752 (Reactome) | ||
C4 binding protein:C4bC2a | REACT_118738 (Reactome) | |||
C4 binding protein:protein S | Arrow | REACT_118836 (Reactome) | ||
C4-binding protein:C4b | Arrow | REACT_118738 (Reactome) | ||
C4-binding protein:C4b | Arrow | REACT_118763 (Reactome) | ||
C4-binding protein:C4b | REACT_118647 (Reactome) | |||
C4a | Arrow | REACT_8002 (Reactome) | ||
C4b with hydrolysed thioester | Arrow | REACT_163768 (Reactome) | ||
C4b, C3b | REACT_118575 (Reactome) | |||
C4b-binding protein:Factor I | Arrow | REACT_118647 (Reactome) | ||
C4b-binding protein:Factor I | REACT_118719 (Reactome) | |||
C4b-binding protein | Arrow | REACT_118719 (Reactome) | ||
C4b-binding protein | REACT_118752 (Reactome) | |||
C4b-binding protein | REACT_118763 (Reactome) | |||
C4b-binding protein | REACT_118836 (Reactome) | |||
C4b:C2a:C3b | Arrow | REACT_8022 (Reactome) | ||
C4bC2a, C3bBb | REACT_118580 (Reactome) | |||
C4bC2a, C3bBb | REACT_118782 (Reactome) | |||
C4c, C3f | Arrow | REACT_118673 (Reactome) | ||
C4c | Arrow | REACT_118719 (Reactome) | ||
C4d, iC3b | Arrow | REACT_118673 (Reactome) | ||
C4d | Arrow | REACT_118719 (Reactome) | ||
C5 convertases | mim-catalysis | REACT_7989 (Reactome) | ||
C5a | Arrow | REACT_7989 (Reactome) | ||
C5b:C6 complex | Arrow | REACT_7976 (Reactome) | ||
C5b:C6 complex | REACT_7950 (Reactome) | |||
C5b:C6:C7 complex | Arrow | REACT_7950 (Reactome) | ||
C5b:C6:C7 complex | Arrow | REACT_7982 (Reactome) | ||
C5b:C6:C7 complex | REACT_163759 (Reactome) | |||
C5b:C6:C7 complex | REACT_7946 (Reactome) | |||
C5b:C6:C7 complex | REACT_7982 (Reactome) | |||
C5b:C6:C7:C8 complex | Arrow | REACT_7946 (Reactome) | ||
C5b:C6:C7:C8 complex | REACT_163829 (Reactome) | |||
C5b:C6:C7:C8 complex | REACT_7988 (Reactome) | |||
C5b | Arrow | REACT_7989 (Reactome) | ||
C5b | REACT_7976 (Reactome) | |||
C6 | REACT_7976 (Reactome) | |||
C7(22-843) | REACT_7950 (Reactome) | |||
C8 | REACT_163870 (Reactome) | |||
C8 | REACT_7946 (Reactome) | |||
C9(22-559) | REACT_163829 (Reactome) | |||
C9(22-559) | REACT_163870 (Reactome) | |||
C9(22-559) | REACT_7988 (Reactome) | |||
CD46 | REACT_118575 (Reactome) | |||
CD55 | REACT_118782 (Reactome) | |||
CD59:C5b-C9 | Arrow | REACT_163829 (Reactome) | ||
CD59 | REACT_163829 (Reactome) | |||
CFB(26-259) | Arrow | REACT_7981 (Reactome) | ||
CFB(26-259) | Arrow | REACT_8026 (Reactome) | ||
CFB(26-764) | REACT_7966 (Reactome) | |||
CFB(26-764) | REACT_8013 (Reactome) | |||
CFB(260-764) | Arrow | REACT_118584 (Reactome) | ||
CFB(260-764) | Arrow | REACT_118641 (Reactome) | ||
CFB(260-764) | Arrow | REACT_118692 (Reactome) | ||
CFB(260-764) | Arrow | REACT_118727 (Reactome) | ||
CFH | Arrow | REACT_118650 (Reactome) | ||
CFH | REACT_118604 (Reactome) | |||
CFH | REACT_118712 (Reactome) | |||
CFI(19-335) | REACT_118674 (Reactome) | |||
CFI(340-583) | REACT_118674 (Reactome) | |||
CR1:C3b | Arrow | REACT_118692 (Reactome) | ||
CR1:C3bBb, C4bC2a complexes | Arrow | REACT_118580 (Reactome) | ||
CR1:C3bBb, C4bC2a complexes | REACT_118692 (Reactome) | |||
CR1:C4b | Arrow | REACT_118692 (Reactome) | ||
CR1:iC3b | REACT_163860 (Reactome) | |||
CR1 | Arrow | REACT_163860 (Reactome) | ||
CR1 | REACT_118580 (Reactome) | |||
Ca2+ | REACT_163715 (Reactome) | |||
Ca2+ | REACT_163747 (Reactome) | |||
Ca2+ | REACT_163758 (Reactome) | |||
Ca2+ | REACT_7983 (Reactome) | |||
Cell
surface:C3b:Factor Bb:Properdin | Arrow | REACT_8018 (Reactome) | ||
Cell
surface:C3b:Factor Bb:Properdin | REACT_7986 (Reactome) | |||
Cell
surface:C3b:Factor Bb:Properdin | mim-catalysis | REACT_7986 (Reactome) | ||
Cell
surface:C3b:Factor Bb | Arrow | REACT_8026 (Reactome) | ||
Cell
surface:C3b:Factor Bb | REACT_118710 (Reactome) | |||
Cell
surface:C3b:Factor Bb | REACT_8018 (Reactome) | |||
Cell
surface:C3b:Factor B complex | Arrow | REACT_7966 (Reactome) | ||
Cell
surface:C3b:Factor B complex | REACT_8026 (Reactome) | |||
Cell surface:FH,FHR3:C3b | Arrow | REACT_118727 (Reactome) | ||
Cell surface:FH,FHR3:C3b | Arrow | REACT_118815 (Reactome) | ||
Cell surface:FH,FHR3:C3bBb | Arrow | REACT_118710 (Reactome) | ||
Cell surface:FH,FHR3:C3bBb | REACT_118727 (Reactome) | |||
Cell surface:FH,FHR3:C3b | REACT_118844 (Reactome) | |||
Cell surface:C3b | Arrow | REACT_25075 (Reactome) | ||
Cell surface:C3b | REACT_118815 (Reactome) | |||
Cell surface:C3b | REACT_7966 (Reactome) | |||
Cell surface:C3b | REACT_8022 (Reactome) | |||
Cell surface:C4b:C2a | Arrow | REACT_118641 (Reactome) | ||
Cell surface:C4b:C2a | Arrow | REACT_8014 (Reactome) | ||
Cell surface:C4b:C2a | REACT_118752 (Reactome) | |||
Cell surface:C4b:C2a | REACT_8022 (Reactome) | |||
Cell surface:C4b | Arrow | REACT_118641 (Reactome) | ||
Cell surface:C4b | Arrow | REACT_25166 (Reactome) | ||
Cell surface:C4b | REACT_8014 (Reactome) | |||
Cell surface | REACT_25075 (Reactome) | |||
Cell surface | REACT_25166 (Reactome) | |||
Complement Factor 4 | REACT_8002 (Reactome) | |||
Complement factor
I:Cell surface:FH,FHR3:C3b | Arrow | REACT_118844 (Reactome) | ||
Complement factor
I:Cell surface:FH,FHR3:C3b | REACT_118841 (Reactome) | |||
Complement factor
I:Cell surface:FH,FHR3:C3b | mim-catalysis | REACT_118841 (Reactome) | ||
Complement factor I:Factor H:C3b | Arrow | REACT_118583 (Reactome) | ||
Complement factor I:Factor H:C3b | REACT_118650 (Reactome) | |||
Complement factor I:Factor H:C3b | mim-catalysis | REACT_118650 (Reactome) | ||
Complement factor 3 | REACT_7948 (Reactome) | |||
Complement factor 3 | REACT_7986 (Reactome) | |||
Complement factor 3 | REACT_7990 (Reactome) | |||
Complement factor 3 | REACT_8007 (Reactome) | |||
Complement factor 5 | REACT_7989 (Reactome) | |||
Complement factor D | mim-catalysis | REACT_7981 (Reactome) | ||
Complement factor D | mim-catalysis | REACT_8026 (Reactome) | ||
Complement factor I | Arrow | REACT_118650 (Reactome) | ||
Complement factor I | Arrow | REACT_118673 (Reactome) | ||
Complement factor I | Arrow | REACT_118674 (Reactome) | ||
Complement factor I | Arrow | REACT_118719 (Reactome) | ||
Complement factor I | Arrow | REACT_118841 (Reactome) | ||
Complement factor I | REACT_118583 (Reactome) | |||
Complement factor I | REACT_118631 (Reactome) | |||
Complement factor I | REACT_118647 (Reactome) | |||
Complement factor I | REACT_118844 (Reactome) | |||
DAF:C3 convertase complexes | Arrow | REACT_118782 (Reactome) | ||
DAF:C3 convertase complexes | REACT_118584 (Reactome) | |||
DAF:C3b | Arrow | REACT_118584 (Reactome) | ||
DAF:C4b | Arrow | REACT_118584 (Reactome) | ||
FCN1 ligand | REACT_163715 (Reactome) | |||
FCN1:MASP2 dimer:MASP1 dimer | REACT_163715 (Reactome) | |||
FCN1:MASPs:Ca2+:FCN1 ligand | Arrow | REACT_163715 (Reactome) | ||
FCN2 ligand | REACT_163747 (Reactome) | |||
FCN2:MASP2 dimer:MASP1 dimer | REACT_163747 (Reactome) | |||
FCN2:MASPs:Ca2+:FCN2 ligand | Arrow | REACT_163747 (Reactome) | ||
FCN3 ligand | REACT_163758 (Reactome) | |||
FCN3:MASP2 dimer:MASP1 dimer | REACT_163758 (Reactome) | |||
FCN3:MASPs:Ca2+:FCN3 ligand | Arrow | REACT_163758 (Reactome) | ||
FH, FHR-3 | Arrow | REACT_118841 (Reactome) | ||
FH, FHR-3 | REACT_118710 (Reactome) | |||
FH, FHR-3 | REACT_118815 (Reactome) | |||
Factor H:C3b | Arrow | REACT_118712 (Reactome) | ||
Factor H:C3b | REACT_118583 (Reactome) | |||
Factor H:Host cell surface | Arrow | REACT_118604 (Reactome) | ||
Factor H:Host cell surface | Arrow | REACT_118710 (Reactome) | ||
Factor H:Host cell surface | Arrow | REACT_118815 (Reactome) | ||
Factor I:MCP,
CR1:C4b, C3b complexes | Arrow | REACT_118631 (Reactome) | ||
Factor I:MCP,
CR1:C4b, C3b complexes | REACT_118673 (Reactome) | |||
Factor I:MCP,
CR1:C4b, C3b complexes | mim-catalysis | REACT_118673 (Reactome) | ||
H2O | REACT_163768 (Reactome) | |||
H2O | REACT_8007 (Reactome) | |||
Host cell surface | REACT_118604 (Reactome) | |||
MBL bound to
mannose-based carbohydrates on bacterial surfaces | Arrow | REACT_7983 (Reactome) | ||
MBL-II:MASP-2
dimer:MASP-1 dimer complex | REACT_7983 (Reactome) | |||
MBL/FCN:activated
MASP:carbohydrate patterns | Arrow | REACT_7965 (Reactome) | ||
MBL/Ficolin:MASPs
bound to carbohydrate patterns | REACT_7965 (Reactome) | |||
MCP, CR1:C4b:C3b complexes | REACT_118631 (Reactome) | |||
MCP, CR1 | Arrow | REACT_118673 (Reactome) | ||
MCP:C3b | Arrow | REACT_118575 (Reactome) | ||
MCP:C4b | Arrow | REACT_118575 (Reactome) | ||
Membrane Attack Complex | Arrow | REACT_7988 (Reactome) | ||
Properdin oligomer | Arrow | REACT_118641 (Reactome) | ||
Properdin oligomer | REACT_8018 (Reactome) | |||
REACT_118575 (Reactome) | Membrane cofactor protein (MCP; CD46) is a widely distributed C3b/C4b-binding cell surface glycoprotein which is a cofactor for Complement factor I. | |||
REACT_118580 (Reactome) | Complement Receptor 1 (CR1) is a widely distributed cell surface protein that is a decay accelerating factor for the conventional (C4bC2a) and alternative (C3bBb) C3 convertases (Coico & Sunshine 2009). | |||
REACT_118583 (Reactome) | Complement factor I binds the factor H:C3b complex. | |||
REACT_118584 (Reactome) | Decay accelerating factor (DAF, CD55) is a widely distributed membrane protein. It accelerates the dissociation of C3bBb and C4C2a, thereby inhibiting the amplification of complement. DAF can bind C3b and Bb but must bind both for efficient decay acceleration. The regulatory function of DAF is believed to be inhibition of activated C3 convertase enzymes rather than binding of inactive proenzymes (Harris et al. 2007). | |||
REACT_118604 (Reactome) | Factor H preferentially binds to host cells and surfaces that have negatively charged cell surface polyanions such as heparin and sialic acid commonly found on host cells (Kazatchkine et al. 1979, Meri & Pangburn 1990). This mediates protection of plasma-exposed host structures. | |||
REACT_118631 (Reactome) | Membrane cofactor protein (MCP) and Complement Receptor 1 (CR1) act as cofactors for the protease activity of complement factor I which binds MCP or CR1 complexes with C3b or C4b, inactivating C3b/C4b. | |||
REACT_118641 (Reactome) | C3b:Bb is naturally labile with a half-life of ~90 s. unless bound to properdin on the cell surface (Medicus et al. 1976). C4bC2a is also unstable, lasting at best a few minutes (Kerr et al. 1980). Decay is associated with the release of the Bb or C2a fragments respectively into the fluid phase. The liberated C3b/C4b is able to re-bind Bb/C2a if Factor B/C2 are present. | |||
REACT_118647 (Reactome) | C4b-binding protein is a cofactor for Complement Factor I, allowing it to bind and thereby mediating C4b proteolysis. | |||
REACT_118650 (Reactome) | Complement factor I cleaves the alpha chain of C3b at two positions, generating inactivated C3b (iC3b) and a small fragment C3f which is released. The majority of the alpha chain is retained as two fragments which are tethered by disulphide bonds. iC3b is proteolytically inactive. | |||
REACT_118673 (Reactome) | Factor I cleaves the truncated alpha (a') chain of C4b between Arg-1336 and Asn-1337 and then again between Arg-956 and Thr-957, producing a 16 kDa fragment known as alpha4, derived from the C terminus of the a' chain, followed by a 27 kDa alpha3 fragment. The remaining alpha 2 (C4d) fragment stays covalently bound to the cell membrane while the complex of disulfide-linked alpha3, alpha4, beta chain and gamma chain are released (C4c) into the fluid phase (Fujita et al. 1978). | |||
REACT_118674 (Reactome) | Complement factor I (CFI) is a complex of one heavy and one light chain, both cleaved from the same precursor peptide. It inactivates complement subcomponents C3b, iC3b and C4b by proteolytic cleavage of the alpha chains of C4b and C3b in the presence of cofactors such as Factor H, C4b binding protein, Complement receptor 1 (CR1) or MCP (CD46). | |||
REACT_118692 (Reactome) | Complement Receptor 1 (CR1) displaces the activated enzyme components Bb and C2a from the conventional and alternative C3 convertases C4bC2a and C3bBb, respectivley. | |||
REACT_118710 (Reactome) | Factor H (FH) binds to C3bBb, leading to displacement of Bb. Complement factor H-related protein 3 (FHR-3) has also been reported to bind C3Bb leading to inhibition of C3Bb C3 convertase activity (Fritsche et al. 2010). FH also acts as a cofactor for the factor I-mediated proteolytic inactivation of C3b to iC3b. | |||
REACT_118712 (Reactome) | Factor H (FH) regulates the alternative pathway C3 convertase C3bBb and its C3b component both in plasma and at host cell surfaces. FH binds to plasma C3b, making it unavailable, and acts as a cofactor for the factor I-mediated proteolytic inactivation of C3b to iC3b. | |||
REACT_118719 (Reactome) | C4b-binding protein is a cofactor in Factor I mediated C4b proteolysis. C4b is cleaved, releasing C4c, leaving C4d bound to the cell surface. | |||
REACT_118727 (Reactome) | Factor H greatly accelerates the displacement (decay) of Complement factor Bb from C3b. | |||
REACT_118738 (Reactome) | C4 binding protein accelerates the decay of C4bC2a in a dose-dependent fashion. The mechanism of this is poorly understood, but is distinct from Factor I mediated degradation of C4b and believed to represent the displacement of C2a from specific binding sites on C4b (Gigli et al. 1979). | |||
REACT_118752 (Reactome) | C4 binding protein accelerates the decay of C4bC2a in a dose-dependent fashion, without causing degradation of C4b, and is presumed to bind to the convertase to mediate this effect. | |||
REACT_118763 (Reactome) | The most abundant form of C4b-binding protein (C4BP) consists of seven alpha-chains (70kDa) and one beta-chain (45kDa) all linked by disulphide bonds to form a native protein with a molecular weight of 570kDa (Hilarp et al. 1989). Each alpha chain can bind C4b; it is not known whether full occupancy is necessary for subsequent events. The beta chain binds and inactivates Protein S, a component of the coagulation system. C4BP down-regulates complement activity in several ways: It binds to C4b thus inhibiting the formation of the classical pathway C3 convertase C4bC2a; it acts as a decay accelerating factor for existing convertases, probably by promoting dissociation of C2a; it is a cofactor in Factor I mediated C4b proteolysis. | |||
REACT_118782 (Reactome) | Decay-accelerating-factor (DAF, CD55) is a membrane- bound complement regulatory protein that inhibits autologous complement cascade activation. It is expressed on all cells that are in close contact with serum complement proteins, but also on cells outside the vascular space and on tumour cells. DAF binds to C3bBb and C4bC2a on cell surfaces, accelerating their dissociation and thereby inhibiting the amplification of complement. DAF can bind C3b and Bb, and must bind both for efficient decay acceleration. Although it can bind the inactive proenzymes C3b and C4b, the regulatory function of DAF is believed to be inhibition of activated C3 convertase enzymes (Harris et al. 2007). | |||
REACT_118815 (Reactome) | Factor H (FH) regulates the alternative pathway C3 convertase C3bBb and its C3b component both in plasma and at host cell surfaces. FH binds to membrane-associated C3b, competing with Factor B and thereby preventing formation of the active C3 convertase C3bBb. In addition, it acts as a cofactor for the Factor I-mediated proteolytic inactivation of C3b to iC3b. | |||
REACT_118836 (Reactome) | The beta subunit of C4b binding protein binds and inactivates Protein S, a vitamin K dependent anticoagulation factor. This may represent part of a mechanism for fine-tuning the process of phagocytosis (Kask et al. 2004). | |||
REACT_118841 (Reactome) | Following the displacement of Bb from C3bBb, Factor I cleaves Factor H-bound C3b producing iC3b, which remains bound to the membrane. The majority of the C3b alpha chain is retained as two fragments which are tethered to the beta chain by disulphide bonds. iC3b is proteolytically inactive and cannot contribute to the complement cascade process, though it still contributes to opsonization. | |||
REACT_118844 (Reactome) | Complement factor I binds to the Factor H:C3b complex. | |||
REACT_163715 (Reactome) | Ficolin-1 (M-ficolin or FCN1) was shown to localize at the cell surface of circulating monocytes and granulocytes, despite lacking an obvious transmembrane domain, (Teh C et al. 2000; Honore C et al. 2010). Ficolin-1 has also been found in human plasma (Honore C et al. 2008; Wittenborn T et al. 2010; Kjaer TR et al. 2011). Monocytes and macrophages, but not immature dendritic cells were reported to secrete Ficolin-1 into the serum (Honore C et al. 2010). Moreover, early studies revealed its presence in secretory granules of peripheral blood monocytes and granulocytes (Liu Y et al. 2005). Soluble Ficolin-1 was found to form a complex with MASP2, while cell surface-bound Ficolin-1 did not associate with MASP (Honore C et al. 2010; Kjaer TR et al. 2011). Ficolin-1 specifically recognizes sialic acid and can bind to acetylated compounds such as N-acetylglucosamine (GlcNAc) and N-acetylgalactosamine (GalNAc) (Garlatti V et al. 2007; Gout E et al. 2010; Kjaer TR et al. 2011). | |||
REACT_163747 (Reactome) | Human ficolin-2 (L-ficolin, P35 or FCN2) is synthesised in the liver and secreted into the bloodstream where it recognizes various capsulated bacteria and exhibits binding specificity for diverse ligands, such as lipoteichoic acid, 1,3-beta-d-glucan, and acetylated compounds [Lynch NJ et al. 2004; Aoyagi Y et al. 2008; Ma YG et al. 2004; Garlatti V et al. 2007; Gout E et al 2010]. Ficolin-2 also binds to apoptotic HL60, U937, and Jurkat cells [Kuraya M, et al. 2005]. | |||
REACT_163758 (Reactome) | Ficolin-3 (H-ficolin, FCN3 or Hakata antigen) activates the lectin pathway of complement similar to mannose-binding lectin. Ficolin-3 is composed by a collagen-like strand and three C-terminal recognition domains which bind to carbohydrates on the target surface. Ficolin-3 circulates in plasma associated with mannan-binding lectin-associated serine proteases (MASPs). Upon ligand binding ficolin-3:MASPs complex triggers activation of the lectin pathway [Matsushita M et al. 2002; Teillet F et al. 2008; Zacho RM et al. 2012]. Ficolin-3 (FCN3 or H-ficolin) can specifically recognize Aerococcus viridans [Tsujimura M et al. 2002; Zacho RM et al. 2012]. Ficolin-3 has been shown to bind to patterns of bacterial polysaccharides such as d-fucose and galactose [Garlatti V et al. 2007]. In adition to pathogenic ligands ficolin-3 was reported to bind to apoptotic Jurkat cells [Kuraya M et al. 2005]. | |||
REACT_163759 (Reactome) | Vitronectin interacts with C5b:C6:C7 complex preventing it from the binding with the cell membrane | |||
REACT_163768 (Reactome) | Cleavage of C4 exposes a highly reactive thioester bond on the C4b molecule. The thioester bond is rapidly inactivated by hydrolysis if C4b does not bind to the target cell surface [Sepp A et al 1993]. | |||
REACT_163829 (Reactome) | CD59, the major inhibitor of the complement membrane attack complex, is an 18–20 kDa glycoprotein, linked to the membrane via a glycosylphosphatidylinositol (GPI)-anchor. It interacts with complement components C8 and C9 during assembly of the membrane attack complex (MAC) and inhibits C9 polymerization, thus preventing the formation of MAC [Lehto T and Meri S. 1993;Rollins SA et al 1991] | |||
REACT_163860 (Reactome) | Factor I (FI) inactivates C3 convertase activity by cleavage C3b producing iC3b, which remains bound to the membrane. A final proteolytic cleavage converts iC3b into two molecules, C3c, which is released into solution, and C3dg, which remains attached to the membrane. This cleavage requires CR1, which serves as a cofactor for cleavage of iC3b by factor I (Medof ME et al. 1982). iC3b and C3dg are active molecules, that can bind CR2 (CD21) to enhance B-cell immunity (Tuveson DA et al.1991; Sarrias MR et al. 2001). | |||
REACT_163870 (Reactome) | Complement proteins C8 and C9 can bind to VTN:C5b:C6:C7 to form soluble C5b-C9 complex in plasma. The vitronectin binding to C5b-C9 complex prevents C9 polymerization by rendering it water-soluble and lytic inactive. | |||
REACT_25075 (Reactome) | Metastable C3b can bind a wide variety of proteins and carbohydrates expressed on biological surfaces (Coico & Sunshine, 2009; Kimball 2010). This is an essentially random event (Dodds & Law, 1998); binding may be to host or microorganism. However, certain surface sugars have greater C3b binding rates, perhaps explaining variations in microorganism suceptibility (Pangburn, M. in The Complement System, Ed. Rother et al. 1998). | |||
REACT_25166 (Reactome) | The cleavage of C4 into C4a and C4b releases an acyl group from the intrachain thioester bond, allowing C4b to bond covalently to any adjacent biological substrates (Dodds & Law 1998). C4 is encoded at two loci, C4A and C4B. The C4b proteins derived from these genes are not identical and have different binding preferences (Law et al 1984, Sepp et al. 1993); C4A-derived C4b binds more efficiently than C4B-derived C4b to amino groups, while C4B-derived C4b is more effective than C4A in binding to hydroxyl groups. The site of C4b deposition is not clearly established (Møller-Kristensen et al. 2003) but generally accepted to be the activating cell membrane surface, though it may be the activating complex itself. | |||
REACT_7946 (Reactome) | ||||
REACT_7948 (Reactome) | C3(H2O):Factor Bb is a C3 convertase, sometimes referred to as the initial C3 convertase (iC3). The Factor Bb component catalyzes the hydrolysis of C3 to produce C3b and C3a. This reaction is not known to be directly coupled to the association of C3b complexes with a cell surface. It is believed that a small proportion of C3b spontaneously associates with the cell surface, otherwise it is rapidly inactivated (Muller-Eberhard 1988). | |||
REACT_7950 (Reactome) | ||||
REACT_7959 (Reactome) | C2 is cleaved into the large C2a and the small C2b fragment. This irreversible, extracellular reaction can be catalyzed by activated MBL, generated through the lectin pathway of complement activation (Vorup-Jensen et al. 2000), and by activated C1, generated through the classical pathway (Nasagawa and Stroud 1977). N.B. Early literature refers to the larger fragment of C2 as C2a. However, complement scientists decided that the smaller of all C fragments should be designated with an 'a', the larger with a 'b', changing the nomenclature for C2. For this reason recent literature may refer to the larger C2 fragment as C2b, and the classical C3 convertase as C4bC2b. Throughout this pathway, Reactome uses the current (Feb 2012) Uniprot names which adhere to the original naming practice. | |||
REACT_7965 (Reactome) | MBL or ficolins binding to carbohydrates on the target surface results in conformational changes in the lectin:MASPs complex. It in turn promotes a cleavage of proenzyme form of MASP between the CCP2 and the serine protease domains, which results in the generation of the active form. The active form of MASP-2 is able to cleave C4 and C2 to generate the C3 convertase (Vorup-Jensen T et al. 2000; Chen CB and Wallis R 2004). The active form of MASP-1 was shown to facilitate the complement activation by either direct cleavage of complex-bound MASP-2 or cleavage of C2 bound to C4 (Matsushita M et al. 2000; Heja D et al. 2012). | |||
REACT_7966 (Reactome) | C3b on a surface binds Factor B from solution to form a complex (Schreiber et al. 1978; Muller-Eberhard 1988). | |||
REACT_7976 (Reactome) | ||||
REACT_7977 (Reactome) | In this irreversible reaction, the activated C1r subunit of the C1:antibody:antigen complex cleaves the C1s subunit of the complex, activating it in turn (Ziccardi and Cooper 1976). The resulting complex is a C4 activator. | |||
REACT_7978 (Reactome) | C1 activation requires interaction with two separate Fc domains, so pentavalent IgM antibody is far more efficient at complement activation than IgG antibody (Muller-Eberhard and Kunkel 1961). Antibody binding results in a conformational change in the C1r component of the C1 complex and a proteolytic cleavage of C1r, activating it (Ziccardi and Cooper 1976). This reaction is irreversible under physiological conditions. | |||
REACT_7981 (Reactome) | Factor D, a constitutively active serine protease found in trace amounts in the blood, cleaves a specific Arg-Lys bond in the Factor B component of the soluble C3(H2O):Factor B complex, yielding C3(H2O):Factor Bb and an inactive polypeptide, Factor Ba (Fearon and Austin 1975; Lesavre and Muller-Eberhard 1978; Lesavre et al. 1979; Schreiber et al. 1978). | |||
REACT_7982 (Reactome) | ||||
REACT_7983 (Reactome) | The MBL polypeptide chain consists of a short N-terminal cysteine-rich region, a collagen-like region comprising 19 Gly-X-Y triplets, a 34-residue hydrophobic stretch, and a C-terminal C-type lectin domain. MBL monomers associate via their cysteine-rich and collagen-like regions to form homotrimers, and these in turn associate into oligomers. The predominant oligomers found in human serum contain three (MBL-I) or four (MBL-II) homotrimers (Fujita et al. 2004; Teillet et al. 2005). Extracellular MBL oligomers circulate in plasma in complexes with MASP1/2. The carbohydrate recognition domain (CRD) of MBL binds carbohydrates with 3- and 4- OH groups in the pyranose ring, such as mannose and N-acetyl-D-glucosamine, in the presence of Ca2+. Such motifs occur on the surfaces of viruses, bacteria, fungi and protozoa. The affinity of any one MBL binding site for a carbohydrate ligand is low, but interaction between multiple binding sites on an MBL oligomer and a repetitive carbohydrate motif on a target surface allow high-avidity binding. The specificity of the MBL binding site (it does not bind glucose or sialic acid) and the requirement for a repeated target motif may account for the failure of MBL to bind human glycoproteins under normal conditions (Petersen et al. 2001). This reaction in particular represents the interaction of MBL with bacterial mannose repeats. | |||
REACT_7986 (Reactome) | The complex of C3b:Factor Bb, stabilized on the cell surface by properdin, catalyzes the cleavage of C3 to yield C3b and C3a. The C3b is recruited to the C3b:Factor B complex through its interaction with properdin (Daha et al. 1976; Medicus et al. 1976; Hourcade 2006), yielding the alternate C5 convertase. | |||
REACT_7988 (Reactome) | The membrane attack complex is composed of one C5:C6:C7:C8 complex and between 12-15 C9 molecules (Podack et al. 1982 - 12 represented in this reaction). | |||
REACT_7989 (Reactome) | The same complexes as for C3 activation are employed for the cleavage of C5. C3 convertases with an additional C3b molecule covalently deposited in the immediate vicinity form the C5 convertases C3bBbC3b and C4b2aC3b, respectively. The second C3b acts like an anvil for C5: it interacts with C5 and presents C5 in the correct conformation for cleavage by the C2a or Bb enzyme. | |||
REACT_7990 (Reactome) | C4b and C2a bind to form the classical pathway C3-convertase (C4b2a complex), C3b and the Bb fragment of Factor B form the alternative pathway C3 convertase. The C3(H2O):Bb C3 convertase is sometimes called the initiating convertase, and the C5 convertases also have C3 convertase activity (Rawal & Pangburn 2001). | |||
REACT_8002 (Reactome) | The alpha chain of C4 is cleaved, releasing an N-terminal portion of this chain as C4a. The beta and gamma chains are not cleaved and remain linked to the alpha chain by disulfide bonds (Nagasawa et al. 1976, 1980). The resulting C4b heterotrimer undergoes a gross conformational change; the internal thioester in C4b becomes exposed and able to form covalent bonds with surrounding molecules (Law and Dodds 1997). A large proportion of the bonds formed are with water, but some will attach C4b to biological surfaces (Rother et al. 1998). This irreversible reaction can be catalyzed by activated MBL, generated through the lectin pathway of complement activation (Fujita et al. 2004; Hajela et al. 2002), and by activated C1, generated through the classical pathway (Muller-Eberhard and Lepow 1965). N.B. Humans have two highly polymorphic loci for Complement factor 4, C4A and C4B. C4A alleles carry the Rodgers (Rg) blood group antigens while the C4B alleles carry the Chido (Ch) blood group antigens. The two loci encode non identical C4 peptides; C4 derived from C4A reacts more rapidly with the amino groups of peptide antigens while C4B allotypes react more rapidly with the hydroxyl group of carbohydrate antigens. The names of the two loci are always represented in uppercase. C4a and C4b refer to the peptide products of Complement Factor 4 cleavage. | |||
REACT_8007 (Reactome) | The thioester linkage between cysteine residue 1010 and glutamine residue 1013 in the alpha chain of Complement factor 3 (C3) can spontaneously hydrolyze, yielding so-called C3(H2O) (Tack et al. 1980; Pangburn & Muller-Eberhard 1980; Pangburn et al. 1981). Thioester bond hydrolysis causes conformational rearrangements that give C3(H2O) the ability to bind Factor B. The spontaneous hydrolysis rate of C3 under physiological conditions and temperature is about l% per hour, thus the C3b-like properties of C3(H2O) provide a continuous low level initiation of the alternative pathway of complement activation (Pangburn & Muller-Eberhard 1983). If not bound by Factor B, C3(H2O) binds Factor H and is inactivated by Factor I | |||
REACT_8013 (Reactome) | Thioester bond hydrolysis causes conformational rearrangements that give C3(H2O) the ability to bind Factor B (Schreiber et al. 1978). The spontaneous hydrolysis rate of C3 under physiological conditions and temperature is about l% per hour, thus the C3b-like properties of C3(H2O) provide a continuous low level initiation of the alternative pathway of complement activation (Pangburn & Muller-Eberhard 1983). | |||
REACT_8014 (Reactome) | C4b and C2a form a complex termed the classical pathway C3 convertase (Muller-Eberhard et al. 1967). C2a that fails to bind C4b is rapidly inactivated. | |||
REACT_8018 (Reactome) | C3b:Bb is naturally labile with a half-life of ~90 s; association of the complex with properdin extends the half-life to ~30 min. (Medicus et al. 1976). Properdin is found in the blood as a mixture of multivalent oligomers: 30% dimers, 45% trimers, 10% tetramers, and 15% higher oligomers. Monomers associate with one another in a head-to-tail arrangement, producing closed circular structures (Smith et al. 1984). These features suggest that the properdin oligomer associated with a C3b:Bb complex on a surface such as a cell membrane can facilitate recruitment of additional C3b:Bb complexes to the site (Farries et al. 1988; Hourcade 2006). | |||
REACT_8022 (Reactome) | C5 convertases are serine proteases that cleave C5 with high efficiency; the C3 convertases can cleave C5 but have a poor affinity for C5, with a Km of 6-9 microM. The high affinity C5 convertases are generated when the low affinity C3/C5 convertases such as C4b:C2a deposit C3b by cleaving native C3. These C3b-containing C3/C5 convertases have Km values of 0.005 microM, well below the normal concentration of C5 in blood (0.37 microM). They have very low Vmax rates, just one C5 cleaved per 1–4 min per enzyme (Rawal & Pangburn 1998). | |||
REACT_8026 (Reactome) | Factor D, a constitutively active serine protease found in trace amounts in the blood, cleaves a specific Arg-Lys bond in the Factor B component of the cell surface-associated C3b:Factor B complex, yielding the alternate C3 convertase C3bBb on the surface and releasing an inactive polypeptide, Factor Ba (Lesavre and Muller-Eberhard 1978; Lesavre et al. 1979; Schreiber et al. 1978). | |||
VTN(20-?) | REACT_163759 (Reactome) | |||
VTN:C5b:C6:C7:C8:C9 | Arrow | REACT_163870 (Reactome) | ||
VTN:C5b:C6:C7 | Arrow | REACT_163759 (Reactome) | ||
VTN:C5b:C6:C7 | REACT_163870 (Reactome) | |||
iC3b | Arrow | REACT_118650 (Reactome) | ||
iC3b | Arrow | REACT_118841 (Reactome) | ||
thioester-C1010-Q1013-C4b | Arrow | REACT_8002 (Reactome) | ||
thioester-C1010-Q1013-C4b | REACT_118763 (Reactome) | |||
thioester-C1010-Q1013-C4b | REACT_163768 (Reactome) | |||
thioester-C1010-Q1013-C4b | REACT_25166 (Reactome) |