EC 126.96.36.199 - Sterol 24-C-methyltransferase
IntEnz Enzyme Nomenclature
21128 [IUBMB]5α-cholesta-8,24-dien-3β-ol5alpha-cholesta-8,24-dien-3beta-olName origin: UniProt - CHECKED (C)Formula: C27H44O
Charge: 0ChEBI compound status: CHECKED (C)S-adenosyl-L-methionineS-adenosyl-L-methionineName origin: UniProt - CHECKED (C)Formula: C15H23N6O5S
Charge: 1ChEBI compound status: CHECKED (C)<?>24-methylene-5α-cholest-8-en-3β-ol24-methylene-5alpha-cholest-8-en-3beta-olName origin: UniProt - CHECKED (C)Formula: C28H46O
Charge: 0ChEBI compound status: CHECKED (C)S-adenosyl-L-homocysteineS-adenosyl-L-homocysteineName origin: UniProt - CHECKED (C)Formula: C14H20N6O5S
Charge: 0ChEBI compound status: CHECKED (C)
Requires glutathione. Acts on a range of sterols with a 24(25)-double bond in the sidechain. While zymosterol is the preferred substrate it also acts on desmosterol, 5α-cholesta-7,24-dien-3β-ol, 5α-cholesta-5,7,24-trien-3β-ol, 4α-methylzymosterol and others. S-Adenosyl-L-methionine attacks the Si-face of the 24(25) double bond and the C-24 hydrogen is transferred to C-25 on the Re face of the double bond.
Links to other databases
Isolation and purification of an S-adenosylmethionine:Δ24-sterol methyltransferase from yeast.J. Biol. Chem. 244: 6334-6340 (1969). [PMID: 5354959]
Mechanism and structural requirements for transformations of substrates by the S-adenosyl-L-methionine:Δ24(25)-sterol methyl transferase enzyme from Saccharomyces cerevisiae.Biochim. Biophys. Acta 1299: 313-324 (1996). [PMID: 8597586]
Stereochemical features of C-methylation on the path to Δ24(28)-methylene and Δ24(28)-ethylidene sterols: studies on the recombinant phytosterol methyl transferase from Arabidopsis thaliana.Tetrahedron Lett. 38: 6115-6118 (1997).
Two families of sterol methyltransferases are involved in the first and the second methylation steps of plant biosynthesis.Eur. J. Biochem. 256: 88-96 (1998). [PMID: 9746350]
Overexpression, purification, and stereochemical studies of the recombinant S-adenosyl-L-methionine:Δ24(25)- to Δ24(28)-sterol methyl transferase enzyme from Saccharomyces cerevisiae sterol methyl transferase.Arch. Biochem. Biophys. 353: 297-311 (1998). [PMID: 9606964]
[EC 188.8.131.52 created 1972, modfied 2001]