IUBMB Enzyme Nomenclature


Accepted name: squalene methyltransferase

Reaction: 2 S-adenosyl-L-methionine + squalene = 2 S-adenosyl-L-homocysteine + 3,22-dimethyl-1,2,23,24-tetradehydro-2,3,22,23-tetrahydrosqualene (overall reaction)
(1a) S-adenosyl-L-methionine + squalene = S-adenosyl-L-homocysteine + 3-methyl-1,2-didehydro-2,3-dihydrosqualene
(1b) S-adenosyl-L-methionine + 3-methyl-1,2-didehydro-2,3-dihydrosqualene = S-adenosyl-L-homocysteine + 3,22-dimethyl-1,2,23,24-tetradehydro-2,3,22,23-tetrahydrosqualene

For diagram of reaction click here.

Other name(s): TMT-1; TMT-2

Systematic name: S-adenosyl-L-methionine:squalene C-methyltransferase

Comments: Two isoforms differing in their specificity were isolated from the green alga Botryococcus braunii BOT22. TMT-1 gave more of the dimethylated form whereas TMT2 gave more of the monomethylated form.

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


1. Niehaus, T.D., Kinison, S., Okada, S., Yeo, Y.S., Bell, S.A., Cui, P., Devarenne, T.P. and Chappell, J. Functional identification of triterpene methyltransferases from Botryococcus braunii race B. J. Biol. Chem. 287 (2012) 8163-8173. [PMID: 22241476]

[EC created 2012]

Return to EC 2.1.1 home page
Return to EC 2.1 home page
Return to EC 2 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page