IUBMB Enzyme Nomenclature


Accepted name: pitrilysin

Reaction: Preferential cleavage of -Tyr16 Leu- and -Phe25 Tyr-bonds of oxidized insulin B chain. Also acts on other substrates of less than 7 kDa such as insulin and glucagon

Other name(s): Escherichia coli protease III; protease Pi; proteinase Pi; PTR; Escherichia coli metalloproteinase Pi

Comments: From the periplasmic space of Escherichia coli. Inhibited by EDTA and 1,10-phenanthroline; not thiol-dependent. Formerly EC Type example of peptidase family M16

Links to other databases: BRENDA, EXPASY, KEGG, MEROPS, Metacyc, PDB, CAS registry number: 81611-78-1


1. Finch, P.W., Wilson, R.E., Brown, K., Hickson, I.D. and Emmerson, P.T. Complete nucleotide sequence of the Escherichia coli ptr gene encoding protease III. Nucleic Acids Res. 14 (1986) 7695-7703. [PMID: 3534791]

2. Affholter, J.A., Fried, V.A. and Roth, R.A. Human insulin-degrading enzyme shares structural and functional homologies with E. coli protease III. Science 242 (1988) 1415-1418. [PMID: 3059494]

3. Becker, A.B. and Roth, R.A. An unusual active site identified in a family of zinc metalloendopeptidases. Proc. Natl. Acad. Sci. USA 89, (1992) 3835-3839. [PMID: 1570301]

4. Ding, L., Becker, A.B., Suzuki, A. and Roth, R.A. Comparison of the enzymatic and biochemical properties of human insulin-degrading enzyme and Escherichia coli protease III. J. Biol. Chem. 267 (1992) 2414-2420. [PMID: 1733942]

5. Anastasi, A., Knight, C.G. and Barrett, A.J. Characterization of the bacterial metalloendopeptidase pitrilysin by use of a continuous fluorescence assay. Biochem. J. 290 (1993) 601-607. [PMID: 7680857]

[EC created 1992 as EC, transferred 1993 to EC (EC created 1992, incorporated 1993)]

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