title: Is the membrane attack complex of complement an enzyme?
abstract: Recent studies on the functional activities of the membrane attack complex of complement, C5b-9, are reviewed. A new speculative hypothesis has been advanced to account for the ability of complement to mediate lysis of various targets. This hypothesis has three major elements: 1) that the membrane attack complex is an enzyme; 2) that the substrate for this putative enzyme is a membrane constituent; 3) that the substrate specificity of the putative enzyme is dependent on the species source of individual complement components within the C5b-9 complex.
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000276:immunology / Q000378:metabolism; D015938:Complement Membrane Attack Complex; D003165:Complement System Proteins / Q000378:metabolism*; D003602:Cytotoxicity, Immunologic; D004798:Enzymes / Q000378:metabolism*; D004912:Erythrocytes / Q000276:immunology; D006168:Guinea Pigs; D006461:Hemolysis; D006801:Humans; D008954:Models, Biological; D013379:Substrate Specificity
chemical_list: D015938:Complement Membrane Attack Complex; D004798:Enzymes; D003165:Complement System Proteins