Absence of phospholipase activity in bacteriophage T4

We assayed phospholipase activity in T4Dt+ and in t mutant phage grown under permissive and restrictive conditions. There was no correlation between the presence of the t+ gene product and phospholipase activity. Phospholipase activity in phage lysates could be attributed to the presence of bacterial debris or to the use of commercial DNase which contains phospholipase.