Solubilisation and fractional precipitation of a steroid alpha-ketol oxidase

An alpha-ketol oxidase that converts deoxycorticosterone to pregnenoic acid has been solubilised and fractionally precipitated with polyethylene glycol from rabbit liver microsomes. Maximal activity was obtained with the 12-14% fraction. Activity was linear with cytochrome P-450 concentrations up to 0.2 nmol and was inhibited with carbon monoxide.