MECHANISM OF HUMAN PLACENTAL AROMATASE - A NEW ACTIVE-SITE MODEL

Based on Akhtar's ferric peroxide mechanism and on recent studies in o ur own laboratory, we present a detailed proposal for aromatase action . This picture can account for the known stereochemical consequences a t C-19 observed by others using isotopes of hydrogen and oxygen. The p ostulated process involves anchoring of the 19-hydroxymethyl and 19-ox o groups at the active site by a glutamate residue, which also serves to activate the 19-oxo group for attack by ferric peroxy species in th e third oxidative step.