The enzyme from Xanthobacter sp. strain Py2 is a multicomponent enzyme comprising (1) an NADH reductase, which provides the reductant for O2 activation; (2) a Rieske-type ferredoxin, which is an electron-transfer protein; (3) an oxygenase, which contains the catalytic centre for alkene epoxidation and (4) a small protein of unknown function that is essential for activity. Requires Fe(II). The enzyme oxygenates C2 to C6 aliphatic alkenes. With propene as substrate, the stereospecificity of the epoxypropane formed is 95% (R) and 5% (S).
