Further observations on an ether‐O‐oxidase, formerly called alkyl etherase, from liver tissue.

Abstract

4. The enzyme in solution is unstable, though some activity remains after standing at 00 C for 2-3 days. Activity is lost rapidly by deep freezing, exposure to 2M-NaCl and at a pH more acid than pH 5 0.5. The enzyme does not appear to be a known oxidase obtainable from liver microsomes; it is not for instance part of the inducible mixed oxygenase system, nor a peroxidase or catalase.6. Since there were some similarities in stability with enzymes dealing with protozoal plasmalogens, or with lanosterol or cholesterol, we were led to explore these substrates in detail, with negative results. But a specimen of cholesterol oxidase from the branching bacterium Nocardia gave 0-oxidation with diethylether.