IUBMB Enzyme Nomenclature


Accepted name: 2-carboxy-1,4-naphthoquinone phytyltransferase

Reaction: phytyl diphosphate + 2-carboxy-1,4-naphthoquinone = demethylphylloquinone + diphosphate + CO2

For diagram of reaction click here.

Glossary: 2-carboxy-1,4-naphthoquinone = 1,4-dioxo-2-naphthoic acid

Other name(s): menA (gene name); ABC4 (gene name); 1,4-dioxo-2-naphthoate phytyltransferase; 1,4-diketo-2-naphthoate phytyltransferase

Systematic name: phytyl-diphosphate:2-carboxy-1,4-naphthoquinone phytyltransferase

Comments: This enzyme, found in plants and cyanobacteria, catalyses a step in the synthesis of phylloquinone (vitamin K1), an electron carrier associated with photosystem I. The enzyme catalyses the transfer of the phytyl chain synthesized by EC, geranylgeranyl diphosphate reductase, to 2-carboxy-1,4-naphthoquinone.

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


1. Johnson, T.W., Shen, G., Zybailov, B., Kolling, D., Reategui, R., Beauparlant, S., Vassiliev, I.R., Bryant, D.A., Jones, A.D., Golbeck, J.H. and Chitnis, P.R. Recruitment of a foreign quinone into the A(1) site of photosystem I. I. Genetic and physiological characterization of phylloquinone biosynthetic pathway mutants in Synechocystis sp. PCC 6803. J. Biol. Chem. 275 (2000) 8523-8530. [PMID: 10722690]

2. Shimada, H., Ohno, R., Shibata, M., Ikegami, I., Onai, K., Ohto, M.A. and Takamiya, K. Inactivation and deficiency of core proteins of photosystems I and II caused by genetical phylloquinone and plastoquinone deficiency but retained lamellar structure in a T-DNA mutant of Arabidopsis. Plant J. 41 (2005) 627-637. [PMID: 15686525]

[EC created 2015]

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