3- hydroxy-3-methylglutaryl-CoA synthetase

Hydroxy-3-methylglutaryl-CoA synthetase, like the enzyme that precedes it,... 

Fig. 3. A mechanism for the reaction catalyzed by 3-hydroxy-3-methylglutaryl-CoA synthetase.

Note three features of this reaction. First, the creation of the new stereocenter is stereoselective Only the S enantiomer is formed. Although the acetyl group of each reactant is achiral, their condensation takes place in a chiral environment created by the enzyme 3-hydroxy-3-methylglutaryl-CoA synthetase. Second, hydrolysis of the thioester group of... 

Simunovic V, Zapp J, Rachid S, Krug D, Meiser P, Muller R. Myxovirescin A biosynthesis is directed by hybrid polyketide synthases/nonribosomal peptide synthetase, 3-hydroxy-3-methylglutaryl-CoA synthases, and trans-acting acyltransferases. ChemBioChem. 2006 7 1206-1220. 

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