| Product Name |
3-demethylubiquinol 3-O-methyltransferase |
| Example Structure |
 |
| Synonyms |
2-octaprenyl-3-methyl-5-hydroxy-6-methoxy-1,4-benzoquinone methyltransferase, 5-demethylubiquinone-9 methyltransferase, 5-demethylubiquinone-9-methyltransferase, AtCOQ3, COQ3, Coq3 O-methyltransferase, O-methyltransferase, OMHMB methyltransferase, OMHMB-methyltransferase, S-adenosyl-L-methionine:2-octaprenyl-3-methyl-5-hydroxy-6-methoxy-1,4-benzoquinone-O-methyltransferase, UbiG, UbiG methyltransferase |
| EC Number |
2.1.1.64 |
| CAS Registry Number |
63774-48-1 |
| Comments |
This enzyme is involved in ubiquinone biosynthesis. Ubiquinones from different organisms have a different number of prenyl units (for example, ubiquinone-6 in Saccharomyces, ubiquinone-9 in rat and ubiquinone-10 in human), and thus the natural substrate for the enzymes from different organisms has a different number of prenyl units. However, the enzyme usually shows a low degree of specificity regarding the number of prenyl units. For example, the human COQ3 enzyme can restore biosynthesis of ubiquinone-6 in coq3 deletion mutants of yeast [3]. The enzymes from yeast, Escherichia coli and rat also catalyse the methylation of 3,4-dihydroxy-5-all-trans-polyprenylbenzoate [3] (a reaction that is classified as EC 2.1.1.114, polyprenyldihydroxybenzoate methyltransferase). |
| Cofactor |
|
| History |
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| Reactions |
S-adenosyl-L-methionine + 3-demethylubiquinone-n = S-adenosyl-L- homocysteine + ubiquinone-n. |