Menu
Home
People
Places
Arts
History
Plants & Animals
Science
Life & Culture
Technology
Reference.org
Complement component 5
open-in-new
<h2 id="function">Function</h2> <p>Complement component 5 is the fifth component of complement, which plays an important role in inflammatory and cell killing processes. This protein is composed of alpha and beta polypeptide chains that are linked by a disulfide bridge. An activation peptide, C5a, which is an <a href="/facts/Anaphylatoxin/PA6yC4Ne">anaphylatoxin</a> that possesses potent <a href="/facts/Spasm/62EfFXKP">spasmogenic</a> and <a href="/facts/Chemotaxis/hYPRdPTk">chemotactic</a> activity, is derived from the alpha polypeptide via cleavage with a <a href="/facts/C5-convertase/AePEysmm">C5-convertase</a>. The C5b macromolecular cleavage product can form a complex with the <a href="/facts/Complement_component_6/5crtzdB4">C6 complement component</a>, and this complex is the basis for formation of the membrane attack complex, which includes additional complement components.<a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a> </p> <h2 id="clinical-significance">Clinical significance</h2> <p>Mutations in this gene cause complement component 5 deficiency, a disease where patients show a propensity for severe recurrent infections. Defects in this gene have also been linked to a susceptibility to <a href="/facts/Liver_fibrosis/bkLuLvCD">liver fibrosis</a> and to <a href="/facts/Rheumatoid_arthritis/qFK4Xwv7">rheumatoid arthritis</a>.<a class="footnote-ref" id="fnref:4" href="#fn:4"><sup>4</sup></a> </p> <h2 id="therapeutic-applications">Therapeutic applications</h2> <p>The drug <a href="/facts/Eculizumab/4zPtDUQG">eculizumab</a> (trade name Soliris) prevents cleavage of C5 into C5a and C5b.<a class="footnote-ref" id="fnref:5" href="#fn:5"><sup>5</sup></a> </p> <h2 id="complement-system-pathway">Complement system pathway</h2> <h2 id="further-reading">Further reading</h2> <ul><li>Tack BF, Morris SC, Prahl JW (1979). "Fifth component of human complement: purification from plasma and polypeptide chain structure". <i>Biochemistry</i>. 18 (8): 1490–7. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1021%2Fbi00575a016">10.1021/bi00575a016</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/106884">106884</a>.</li> <li>Fernandez HN, Hugli TE (1978). <a href="https://doi.org/10.1016%2FS0021-9258%2817%2938013-4">"Primary structural analysis of the polypeptide portion of human C5a anaphylatoxin. Polypeptide sequence determination and assignment of the oligosaccharide attachment site in C5a"</a>. <i>J. Biol. Chem</i>. 253 (19): 6955–64. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1016%2FS0021-9258%2817%2938013-4">10.1016/S0021-9258(17)38013-4</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/690134">690134</a>.</li> <li>DiScipio RG (1992). <a href="https://doi.org/10.1016%2FS0021-9258%2818%2941897-2">"Formation and structure of the C5b-7 complex of the lytic pathway of complement"</a>. <i>J. Biol. Chem</i>. 267 (24): 17087–94. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1016%2FS0021-9258%2818%2941897-2">10.1016/S0021-9258(18)41897-2</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/1387399">1387399</a>.</li> <li>Haviland DL, Haviland JC, Fleischer DT, et al. (1991). <a href="https://doi.org/10.4049%2Fjimmunol.146.1.362">"Complete cDNA sequence of human complement pro-C5. Evidence of truncated transcripts derived from a single copy gene"</a>. <i>J. Immunol</i>. 146 (1): 362–8. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.4049%2Fjimmunol.146.1.362">10.4049/jimmunol.146.1.362</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/1984448">1984448</a>.</li> <li>Bohnsack JF, Mollison KW, Buko AM, et al. (1991). <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1149811">"Group B streptococci inactivate complement component C5a by enzymic cleavage at the C-terminus"</a>. <i>Biochem. J</i>. 273 (Pt 3): 635–40. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1042%2Fbj2730635">10.1042/bj2730635</a>. <a href="/facts/PMC_(identifier)/dX1zMt71">PMC</a> <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1149811">1149811</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/1996961">1996961</a>.</li> <li>Lundwall AB, Wetsel RA, Kristensen T, et al. (1985). <a href="https://doi.org/10.1016%2FS0021-9258%2818%2989523-0">"Isolation and sequence analysis of a cDNA clone encoding the fifth complement component"</a>. <i>J. Biol. Chem</i>. 260 (4): 2108–12. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1016%2FS0021-9258%2818%2989523-0">10.1016/S0021-9258(18)89523-0</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/2579066">2579066</a>.</li> <li>Zuiderweg ER, Fesik SW (1989). "Heteronuclear three-dimensional NMR spectroscopy of the inflammatory protein C5a". <i>Biochemistry</i>. 28 (6): 2387–91. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1021%2Fbi00432a008">10.1021/bi00432a008</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/2730871">2730871</a>.</li> <li>Zuiderweg ER, Nettesheim DG, Mollison KW, Carter GW (1989). "Tertiary structure of human complement component C5a in solution from nuclear magnetic resonance data". <i>Biochemistry</i>. 28 (1): 172–85. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1021%2Fbi00427a025">10.1021/bi00427a025</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/2784981">2784981</a>.</li> <li>Haefliger JA, Tschopp J, Vial N, Jenne DE (1989). <a href="https://doi.org/10.1016%2FS0021-9258%2819%2984676-8">"Complete primary structure and functional characterization of the sixth component of the human complement system. Identification of the C5b-binding domain in complement C6"</a>. <i>J. Biol. Chem</i>. 264 (30): 18041–51. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1016%2FS0021-9258%2819%2984676-8">10.1016/S0021-9258(19)84676-8</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/2808363">2808363</a>.</li> <li>Wetsel RA, Lemons RS, Le Beau MM, et al. (1988). "Molecular analysis of human complement component C5: localization of the structural gene to chromosome 9". <i>Biochemistry</i>. 27 (5): 1474–82. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1021%2Fbi00405a012">10.1021/bi00405a012</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/3365401">3365401</a>.</li> <li>Zuiderweg ER, Mollison KW, Henkin J, Carter GW (1988). "Sequence-specific assignments in the 1H NMR spectrum of the human inflammatory protein C5a". <i>Biochemistry</i>. 27 (10): 3568–80. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1021%2Fbi00410a007">10.1021/bi00410a007</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/3408713">3408713</a>.</li> <li>Stewart JL, Kolb WP, Sodetz JM (1987). <a href="https://doi.org/10.4049%2Fjimmunol.139.6.1960">"Evidence that C5b recognizes and mediates C8 incorporation into the cytolytic complex of complement"</a>. <i>J. Immunol</i>. 139 (6): 1960–4. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.4049%2Fjimmunol.139.6.1960">10.4049/jimmunol.139.6.1960</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/3624872">3624872</a>.</li> <li>Buhl AM, Osawa S, Johnson GL (1995). <a href="https://doi.org/10.1074%2Fjbc.270.34.19828">"Mitogen-activated protein kinase activation requires two signal inputs from the human anaphylatoxin C5a receptor"</a>. <i>J. Biol. Chem</i>. 270 (34): 19828–32. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1074%2Fjbc.270.34.19828">10.1074/jbc.270.34.19828</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/7649993">7649993</a>.</li> <li>Babkina IN, Seregin SV, Daniliuk NK, et al. (1995). "[Chemico-enzymatic synthesis, cloning and expression of a gene for an analog of human anaphylatoxin C5a]". <i>Bioorg. Khim</i>. 21 (5): 359–64. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/7661861">7661861</a>.</li> <li>Wang X, Fleischer DT, Whitehead WT, et al. (1995). <a href="https://doi.org/10.4049%2Fjimmunol.154.10.5464">"Inherited human complement C5 deficiency. Nonsense mutations in exons 1 (Gln1 to Stop) and 36 (Arg1458 to Stop) and compound heterozygosity in three African-American families"</a>. <i>J. Immunol</i>. 154 (10): 5464–71. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.4049%2Fjimmunol.154.10.5464">10.4049/jimmunol.154.10.5464</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/7730648">7730648</a>.</li> <li>Oppermann M, Götze O (1995). <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1414921">"Plasma clearance of the human C5a anaphylatoxin by binding to leucocyte C5a receptors"</a>. <i>Immunology</i>. 82 (4): 516–21. <a href="/facts/PMC_(identifier)/dX1zMt71">PMC</a> <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1414921">1414921</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/7835913">7835913</a>.</li> <li>Süsal C, Kirschfink M, Kröpelin M, et al. (1994). <a href="https://doi.org/10.4049%2Fjimmunol.152.12.6028">"Complement activation by recombinant HIV-1 glycoprotein gp120"</a>. <i>J. Immunol</i>. 152 (12): 6028–34. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.4049%2Fjimmunol.152.12.6028">10.4049/jimmunol.152.12.6028</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/7911492">7911492</a>.</li> <li>Arribas J, Arizti P, Castaño JG (1994). <a href="https://doi.org/10.1016%2FS0021-9258%2818%2999955-2">"Antibodies against the C2 COOH-terminal region discriminate the active and latent forms of the multicatalytic proteinase complex"</a>. <i>J. Biol. Chem</i>. 269 (17): 12858–64. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1016%2FS0021-9258%2818%2999955-2">10.1016/S0021-9258(18)99955-2</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/8175701">8175701</a>.</li> <li>Süsal C, Kirschfink M, Kröpelin M, et al. (1996). <a href="https://doi.org/10.1182%2Fblood.V87.6.2329.bloodjournal8762329">"Identification of complement activation sites in human immunodeficiency virus type-1 glycoprotein gp120"</a>. <i>Blood</i>. 87 (6): 2329–36. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1182%2Fblood.V87.6.2329.bloodjournal8762329">10.1182/blood.V87.6.2329.bloodjournal8762329</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/8630395">8630395</a>.</li> <li>Ames RS, Li Y, Sarau HM, et al. (1996). <a href="https://doi.org/10.1074%2Fjbc.271.34.20231">"Molecular cloning and characterization of the human anaphylatoxin C3a receptor"</a>. <i>J. Biol. Chem</i>. 271 (34): 20231–4. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1074%2Fjbc.271.34.20231">10.1074/jbc.271.34.20231</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/8702752">8702752</a>.</li> <li>Fredslund F, Laursen NS, Roversi P, et al. (2008). "Structure of and influence of a tick complement inhibitor on human complement component 5". <i>Nat Immunol</i>. 9 (7): 753–60. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1038%2Fni.1625">10.1038/ni.1625</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/18536718">18536718</a>. <a href="/facts/S2CID_(identifier)/ldJsHa2Y">S2CID</a> <a href="https://api.semanticscholar.org/CorpusID:205361576">205361576</a>.</li></ul> <h2 id="external-links">External links</h2> <ul><li><a href="https://meshb.nlm.nih.gov/record/ui?name=Complement+5">Complement+5</a> at the U.S. National Library of Medicine <a href="/facts/Medical_Subject_Headings/C57g2JuF">Medical Subject Headings</a> (MeSH)</li></ul> <p><i>This article incorporates text from the <a href="/facts/United_States_National_Library_of_Medicine/Hzty0MCX">United States National Library of Medicine</a>, which is in the <a href="/facts/Public_domain/YWKMDKw4">public domain</a>.</i> </p> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>"C5 complement C5 (Homo sapiens (human)) Gene ID: 727". www.ncbi.nlm.nih.gov. 29 November 2020. Retrieved 9 December 2020. <a href="https://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=727" target="_blank">https://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=727</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>Immunology at MCG 1/phagocyt[dead link] <a href="/wiki/Medical_College_of_Georgia" target="_blank">/wiki/Medical_College_of_Georgia</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>"C5 complement C5 (Homo sapiens (human)) Gene ID: 727". www.ncbi.nlm.nih.gov. 29 November 2020. Retrieved 9 December 2020. <a href="https://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=727" target="_blank">https://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=727</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>"C5 complement C5 (Homo sapiens (human)) Gene ID: 727". www.ncbi.nlm.nih.gov. 29 November 2020. Retrieved 9 December 2020. <a href="https://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=727" target="_blank">https://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=727</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>Dubois E, Cohen A (2009). "Eculizumab". Br J Clin Pharmacol. 68 (3): 318–319. doi:10.1111/j.1365-2125.2009.03491.x. PMC 2766470. PMID 19740388. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2766470" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2766470</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> </ol>