Distribution of glycerophospholipid-cholesterol acyltransferase in selected bacterial species.

The distribution of glycerophospholipid-cholesterol acyltransferase in selected bacterial species was examined. Enzyme activity was demonstrated in cell-free growth media from all members of the family Vibrionaceae which were tested except Plesiomonas shigelloides. In each case, enzyme was produced in exponential to early stationary phase and was excluded from Sepharose 6B, indicating a complex of high molecular weight. In a limited survey of other families, Stahylococcus aureus was the only organism outside the Vibrionaceae which was shown to produce the enzyme. In this case, however, the enzyme exhibited much less activity against erythrocyte membranes and appeared to have a lower molecular weight. The reasons for these differences and the importance of the acyltransferase as a biochemical identification tool are discussed.