IUBMB Enzyme Nomenclature


Accepted name: methenyltetrahydromethanopterin cyclohydrolase

Reaction: 5,10-methenyl-5,6,7,8-tetrahydromethanopterin + H2O = 5-formyl-5,6,7,8-tetrahydromethanopterin

For diagram of reaction click here

Glossary: tetrahydromethanopterin

Other name(s): 5,10-methenyltetrahydromethanopterin cyclohydrolase; N5,N10-methenyltetrahydromethanopterin cyclohydrolase; methenyl-H4MPT cyclohydrolase; 5,10-methenyltetrahydromethanopterin 10-hydrolase (decyclizing)

Systematic name: 5,10-methenyltetrahydromethanopterin 10-hydrolase (ring-opening)

Comments: Methanopterin is a pterin analogue. The enzyme is involved in the formation of methane from CO2 in Methanobacterium thermoautotrophicum.

Links to other databases: BRENDA, EAWAG-BBD, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 99533-50-3


1. Donnelly, M.I., Escalante-Semerena, J.C., Rinehart, K.L., Jr. and Wolfe, R.S. Methenyl-tetrahydromethanopterin cyclohydrolase in cell extracts of Methanobacterium. Arch. Biochem. Biophys. 242 (1985) 430-439. [PMID: 4062290]

[EC created 1989]

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