In enzymology, a 3-methyl-2-oxobutanoate hydroxymethyltransferase (EC 2.1.2.11) is an enzyme that catalyzes the chemical reaction The 3 substrates of this enzyme are 5,10-methylenetetrahydrofolate, 3-methyl-2-oxobutanoate, and H2O, whereas its two products are tetrahydrofolate and 2-dehydropantoate.
This enzyme belongs to the family of transferases that transfer one-carbon groups, specifically the hydroxymethyl-, formyl- and related transferases.
The systematic name of this enzyme class is 5,10-methylenetetrahydrofolate:3-methyl-2-oxobutanoate hydroxymethyltransferase.
This enzyme participates in pantothenate and coa biosynthesis.
As of late 2007, 4 structures have been solved for this class of enzymes, with PDB accession codes 1M3U, 1O66, 1O68, and 1OY0.