|Superclasses:||Reactions Classified By Conversion Type → Simple Reactions → Chemical Reactions|
|Reactions Classified By Substrate → Small-Molecule Reactions|
EC Number: 126.96.36.199
Enzymes and Genes:
|Geobacillus stearothermophilus:||S-adenosylmethionine:2-demethylmenaquinol methyltransferase: menH|
|Mycobacterium phlei:||S-adenosylmethionine:2-demethylmenaquinol methyltransferase|
In Pathway: menaquinol-13 biosynthesis
Note that this reaction equation differs from the official Enzyme Commission reaction equation for this EC number, which can be found here .
The direction shown, i.e. which substrates are on the left and right sides, is in accordance with the direction in which it was curated.
Most BioCyc compounds have been protonated to a reference pH value of 7.3. Please see the PGDB Concepts Guide for more information.
Mass balance status: Balanced.
Enzyme Commission Primary Name: demethylmenaquinone methyltransferase
Enzyme Commission Synonyms: S-adenosyl-L-methione-DMK methyltransferase, demethylmenaquinone C-methylase, 2-heptaprenyl-1,4-naphthoquinone methyltransferase, 2-demethylmenaquinone methyltransferase, S-adenosyl-L-methione:2-demethylmenaquinone methyltransferase
Standard Gibbs Free Energy (ΔrG'° in kcal/mol): -20.64 [Latendresse13]
Enzyme Commission Summary:
The enzyme catalyses the last step in menaquinone biosynthesis. It is able to accept substrates with varying polyprenyl side chain length (the chain length is determined by polyprenyl diphosphate synthase) [KoikeTakeshita97]. The enzyme from E. coli also catalyses the conversion of 2-octaprenyl-6-methoxy-1,4-benzoquinone to 2-octaprenyl-3-methyl-6-methoxy-1,4-benzoquinone during the biosynthesis of ubiquinone [Lee97].
Instance reactions of [S-adenosyl-L-methionine + a demethylmenaquinol → S-adenosyl-L-homocysteine + a menaquinol + H+] (188.8.131.52):
i1: demethylmenaquinol-10 + S-adenosyl-L-methionine → menaquinol-10 + S-adenosyl-L-homocysteine + H+ (184.108.40.206)
i2: demethylmenaquinol-6 + S-adenosyl-L-methionine → menaquinol-6 + S-adenosyl-L-homocysteine + H+ (220.127.116.11)
i3: demethylmenaquinol-11 + S-adenosyl-L-methionine → menaquinol-11 + S-adenosyl-L-homocysteine + H+ (18.104.22.168)
i4: demethylmenaquinol-7 + S-adenosyl-L-methionine → menaquinol-7 + S-adenosyl-L-homocysteine + H+ (22.214.171.124)
i5: demethylmenaquinol-12 + S-adenosyl-L-methionine → menaquinol-12 + S-adenosyl-L-homocysteine + H+ (126.96.36.199)
i6: demethylmenaquinol-9 + S-adenosyl-L-methionine → menaquinol-9 + S-adenosyl-L-homocysteine + H+ (188.8.131.52)
i7: S-adenosyl-L-methionine + demethylmenaquinol-8 → S-adenosyl-L-homocysteine + menaquinol-8 + H+ (184.108.40.206)
i8: demethylmenaquinol-13 + S-adenosyl-L-methionine → menaquinol-13 + S-adenosyl-L-homocysteine + H+ (220.127.116.11)
KoikeTakeshita97: Koike-Takeshita A, Koyama T, Ogura K (1997). "Identification of a novel gene cluster participating in menaquinone (vitamin K2) biosynthesis. Cloning and sequence determination of the 2-heptaprenyl-1,4-naphthoquinone methyltransferase gene of Bacillus stearothermophilus." J Biol Chem 272(19);12380-3. PMID: 9139683
Lee97: Lee PT, Hsu AY, Ha HT, Clarke CF (1997). "A C-methyltransferase involved in both ubiquinone and menaquinone biosynthesis: isolation and identification of the Escherichia coli ubiE gene." J Bacteriol 1997;179(5);1748-54. PMID: 9045837
Wissenbach92: Wissenbach U, Ternes D, Unden G (1992). "An Escherichia coli mutant containing only demethylmenaquinone, but no menaquinone: effects on fumarate, dimethylsulfoxide, trimethylamine N-oxide and nitrate respiration." Arch Microbiol 1992;158(1);68-73. PMID: 1444716
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