Molecular function

GO:1990886

Catalysis of the reaction: 3,4-dihydroxy-5-polyprenylbenzoic acid + S-adenosyl-L-methionine = 3-methoxy-4-hydroxy-5-polyprenylbenzoic acid + S-adenosyl-L-homocysteine + H+.

polyprenyldihydroxybenzoate methyltransferase activity

Note that the polyprenyl sidechain substrate for this reaction has a different number of prenyl units in different organisms (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.