2-polyprenyl-6-hydroxyphenol methylase (, ubiG (gene), ubiG methyltransferase, 2-octaprenyl-6-hydroxyphenol methylase) is an enzyme with systematic name S-adenosyl-L-methionine:3-(all-trans-polyprenyl)benzene-1,2-diol 2-O-methyltransferase. This enzyme catalyses the following chemical reaction
UbiG catalyses both methylation steps in ubiquinone biosynthesis in Escherichia coli.