IUBMB Enzyme Nomenclature


Accepted name: thiazole tautomerase

Reaction: 2-[(2R,5Z)-(2-carboxy-4-methylthiazol-5(2H)-ylidene]ethyl phosphate = 2-(2-carboxy-4-methylthiazol-5-yl)ethyl phosphate

For diagram of reaction click here.

Glossary: cThz*-P = 2-[(2R,5Z)-2-carboxy-4-methylthiazol-5(2H)-ylidene]ethyl phosphate
cThz-P = 2-(2-carboxy-4-methylthiazol-5-yl)ethyl phosphate = 4-methyl-5-[2-(phosphonooxy)ethyl]-1,3-thiazole-2-carboxylate

Other name(s): tenI (gene name)

Systematic name: 2-(2-carboxy-4-methylthiazol-5-yl)ethyl phosphate isomerase

Comments: The enzyme catalyses the irreversible aromatization of the thiazole moiety of 2-[(2R,5Z)-(2-carboxy-4-methylthiazol-5(2H)-ylidene]ethyl phosphate.

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


1. Hazra, A.B., Han, Y., Chatterjee, A., Zhang, Y., Lai, R.Y., Ealick, S.E. and Begley, T.P. A missing enzyme in thiamin thiazole biosynthesis: identification of TenI as a thiazole tautomerase. J. Am. Chem. Soc. 133 (2011) 9311-9319. [PMID: 21534620]

[EC created 2012]

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