IUBMB Enzyme Nomenclature


Accepted name: [amino group carrier protein]-ornithine hydrolase

Reaction: [amino group carrier protein]-C-terminal-γ-(L-ornithyl)-L-glutamate + H2O = [amino group carrier protein]-C-terminal-L-glutamate + L-ornithine

Other name(s): lysK (gene name)

Systematic name: [amino group carrier protein]-C-terminal-γ-L-ornithyl-L-glutamate amidohydrolase

Comments: The enzyme participates in an L-arginine biosynthetic pathways in certain species of archaea and bacteria. In all cases known so far the enzyme also catalyses the activity of EC, [amino group carrier protein]-lysine hydrolase.

Links to other databases: BRENDA, EXPASY, ExplorEnz, KEGG, MetaCyc, CAS registry number:


1. Ouchi, T., Tomita, T., Horie, A., Yoshida, A., Takahashi, K., Nishida, H., Lassak, K., Taka, H., Mineki, R., Fujimura, T., Kosono, S., Nishiyama, C., Masui, R., Kuramitsu, S., Albers, S.V., Kuzuyama, T. and Nishiyama, M. Lysine and arginine biosyntheses mediated by a common carrier protein in Sulfolobus. Nat. Chem. Biol. 9 (2013) 277-283. [PMID: 23434852]

2. Yoshida, A., Tomita, T., Atomi, H., Kuzuyama, T. and Nishiyama, M. Lysine biosynthesis of Thermococcus kodakarensis with the capacity to function as an ornithine biosynthetic system. J. Biol. Chem. 291 (2016) 21630-21643. [PMID: 27566549]

[EC created 2019]

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