Phospholipase activity in bacteriophage-infected Escherichia coli. I. Demonstration of a T4 bacteriophage-associated phospholipase.

Phospholipase activity has been found to be associated with T4 phage and T4 ghost particles. The attachment of the phospholipase to the phage persists during purification through cesium chloride gradients and dialysis, indicating that it is firmly bound. The presence of the enzymatic activity on T4 ghosts suggests that it is not normally packaged within the head of the virus. The enzyme has specificity for phosphatidylglycerol and its activity is stimulated by 0.1% Triton X-100 and 20% methanol. It does not have a requirement for Ca(2+) and is inactivated at temperatures above 60 C. The association of the phospholipase with T4 phage grown in a phospholipase-deficient host and its absence on unsuppressed T4amtA3 suggests that it may be phage gene specific.