IUBMB Enzyme Nomenclature


Accepted name: Ni-sirohydrochlorin a,c-diamide reductive cyclase

Reaction: ATP + Ni-sirohydrochlorin a,c-diamide + 3 reduced electron acceptor + H2O = ADP + phosphate + 15,173-seco-F430-173-acid + 3 electron acceptor

For diagram of reaction click here.

Other name(s): cfbC (gene name); cfbD (gene name)

Systematic name: Ni-sirohydrochlorin a,c-diamide reductive cyclo-ligase (ADP-forming)

Comments: The enzyme, studied from the methanogenic archaeon Methanosarcina acetivorans, participates in the biosynthesis of the nickel-containing tetrapyrrole cofactor coenzyme F430, which is required by EC, coenzyme-B sulfoethylthiotransferase.

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


1. Pfaltz, A., Kobelt, A., Huster, R. and Thauer, R.K. Biosynthesis of coenzyme F430 in methanogenic bacteria. Identification of 15,173-seco-F430-173-acid as an intermediate. Eur. J. Biochem. 170 (1987) 459-467. [PMID: 3691535]

2. Zheng, K., Ngo, P.D., Owens, V.L., Yang, X.P. and Mansoorabadi, S.O. The biosynthetic pathway of coenzyme F430 in methanogenic and methanotrophic archaea. Science 354 (2016) 339-342. [PMID: 27846569]

[EC created 2017]

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