Reaction catalyzed by hydroxymethylglutaryl-CoA reductase (NADPH) (1.1.1.34)
+
2
NADPH
+
2
=
+
CoA
+
2
NADP+
D-3-hydroxy-3-methylglutaryl-CoA
+
2 NADPH
+
2 H+
=
(R)-mevalonate
+
CoA
+
2 NADP+