Acetaldehyde oxidation in the absence of pyruvate oxidation factor.

The pyruvate oxidation factor (POF) is required by Streptococcus faecalis, strain 1OC1, in order to oxidize pyruvate to acetate and CO2 using oxygen or another molecule of pyruvate as the oxidant (O'Kane and Gunsalus, 1947, 1948). In order to gain some insight into the role of pyruvate oxidation factor other pyruvate reactions and acetate-producing reactions are being examined. No reliable method of removing pyruvate oxidation factor from enzyme preparations is yet available, so the technique of growing cells in the absence of pyruvate oxidation factor was used to produce cells containing only apoenzyme forms of pyruvate oxidation factor-utilizing enzymes. The ability of such cells to carry out the reaction being studied and the effect of added pyruvate oxidation factor indicate whether or not pyruvate oxidation factor is required. By this method it can be shown that the oxidation of ethanol, or acetaldehyde, to acetate does not require pyruvate oxidation factor. The implications of this finding in relation to a possible site of action of pyruvate oxidation factor are discussed.