dihydromonacolin L carboxylate + reduced [NADPH--hemoprotein reductase] + O2 <=> monacolin L carboxylate + oxidized [NADPH--hemoprotein reductase] + 2 H2O + H(+)
dihydromonacolin l carboxylate + reduced [nadph--hemoprotein reductase] + o2 <=> monacolin l carboxylate + oxidized [nadph--hemoprotein reductase] + 2 h2o + h(+)