title: Evolutionary families of peptidases.
abstract: The available amino acid sequences of peptidases have been examined, and the enzymes have been allocated to evolutionary families. Some of the families can be grouped together in 'clans' that show signs of distant relationship, but nevertheless, it appears that there may be as many as 60 evolutionary lines of peptidases with separate origins. Some of these contain members with quite diverse peptidase activities, and yet there are some striking examples of convergence. We suggest that the classification by families could be used as an extension of the current classification by catalytic type.
authors.affiliation: Department of Biochemistry, Strangeways Research Laboratory, Worts Causeway, Cambridge, U.K.
authors.forename: N D
authors.initials: ND
authors.lastname: Rawlings
authors.forename: A J
authors.initials: AJ
authors.lastname: Barrett
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D016282:Aspartic Acid Endopeptidases / Q000737:chemistry; D005075:Biological Evolution; D003546:Cysteine Endopeptidases / Q000737:chemistry; D016208:Databases, Factual; D010450:Endopeptidases / Q000737:chemistry* / Q000145:classification; D006801:Humans; D008666:Metalloendopeptidases / Q000737:chemistry; D012697:Serine Endopeptidases / Q000737:chemistry
chemical_list: D010450:Endopeptidases; D012697:Serine Endopeptidases; D003546:Cysteine Endopeptidases; D016282:Aspartic Acid Endopeptidases; D008666:Metalloendopeptidases