IUBMB Enzyme Nomenclature


Accepted name: endopeptidase So

Reaction: Hydrolysis of proteins, but not Bz-Tyr-OEt, Ac-Phe-β-naphthylester, or Bz-Arg-OEt

Other names: E. coli cytoplasmic proteinase; proteinase So; Escherichia coli serine proteinase So

Comments: An Escherichia coli cytoplasmic endopeptidase formerly included in EC Inhibited by Tos-Phe-CH2Cl, but not by Tos-Lys-CH2Cl

Links to other databases: BRENDA, EXPASY, KEGG, MEROPS, Metacyc, CAS registry number: 81611-83-8


1. Goldberg, A.L., Swamy, K.H.S., Chung, C.H. and Larimore, F.S. Proteases in Escherichia coli. Methods Enzymol. 80 (1981) 680-702.

2. Chung, C.H. and Goldberg, A.L. Purification and characterization of protease So, a cytoplasmic serine protease in Escherichia coli. J. Bacteriol. 154 (1983) 231-238. [PMID: 6339474]

[EC created 1992 (EC created 1961 as EC, transferred 1972 to EC, modified 1986, part incorporated 1992)]

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