IUBMB Enzyme Nomenclature


Accepted name: atrolysin C

Reaction: Cleavage of His5Leu, His10Leu, Ala14Leu, Tyr16Leu and Gly23Phe bonds in B chain of insulin. With small molecule substrates prefers hydrophobic residue at P2' and small residue such as Ala, Gly at P1

Other names: Crotalus atrox metalloendopeptidase c; hemorrhagic toxin c and d

Comments: A 24 kDa hemorrhagic endopeptidase from the venom of the western diamondback rattlesnake (Crotalus atrox) that digests type IV collagen, and exists as two forms, c and d. Phosphoramidon inhibits in the 0.1 mM range. In peptidase family M12 (astacin family). Hemorrhagic toxin-2 of C. ruber ruber has the same Mr and specificity and is a homologue [4,6]

Links to other databases: BRENDA, EXPASY, KEGG, MEROPS, Metacyc, PDB, CAS registry number: 158886-17-0


1. Bjarnason, J.B. and Tu, A.T. Hemorrhagic toxins from western diamondback rattlesnake (Crotalus atrox) venom: isolation and characterization of five toxins and the role of zinc in hemorrhagic toxin e. Biochemistry 17 (1978) 3395-3404. [PMID: 210790]

2. Fox, J.W., Campbell, R., Beggerly, L. and Bjarnason, J.B. Substrate specificities and inhibition of two hemorrhagic zinc proteases Ht-c and Ht-d from Crotalus atrox venom. Eur. J. Biochem.156 (1986) 65-72. [PMID: 3514216]

3. Bjarnason, J.B. and Fox, J.W. Characterization of two hemorrhagic zinc proteinases, toxin c and toxin d, from western diamondback rattlesnake (Crotalus atrox) venom. Biochim. Biophys. Acta 911 (1987) 356-363. [PMID: 3101740]

4. Mori, N., Nikai, T., Sugihara, H. and Tu, A.T. Biochemical characterization of hemorrhagic toxins with fibrinogenase activity isolated from Crotalus ruber ruber venom. Arch. Biochem. Biophys. 253 (1987) 108-121. [PMID: 2949699]

5. Shannon, J.D., Baramova, E.N., Bjarnason, J.B. and Fox, F.W. Amino acid sequence of a Crotalus atrox venom metalloproteinase which cleaves type IV collagen and gelatin. J. Biol. Chem. 264 (1989) 11575-11583. [PMID: 2745407]

6. Takeya, H., Onikura, A., Nikai, T., Sugihara, H. and Iwanaga, S. Primary structure of a hemorrhagic metalloproteinase, HT-2, isolated from the venom of Crotalus ruber ruber. J. Biochem. (Tokyo) 108 (1990) 711-719. [PMID: 2081731]

[EC created 1992]

Return to EC 3.4.24 home page
Return to EC 3.4 home page
Return to EC 3 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page