Mechanism of 17α-Hydroxylase/17,20-Lyase — An initial geometric perspective for the Lyase of the C(17)---C(20) bond of C21 steroids

Using the novel ‘substrate-heme complex’ approach1, the mechanism of 17α-Hydroxylase/17,20-Lyase (P-45017α), in particular the lyase of the C(17)---C(20) bond, is considered from a feometric perspective. The results of the study appear to suggest that the final oxidative step in the lyase of the C(17)---C(20) bond involves the use of a ferroxy attacking species as opposed to peroxy or a mixture of ferroxy and peroxy, an observation which is consistent with results previously obtained with Aromatase1.