Different effects of chloramphenicol, dactinomycin, and streptovitacin A on synthesis of tumor and virion antigens in SV40 virus-infected cells.

Abstract

Streptovitacin A, an hydroxylated analogue of cycloheximide, completely suppressed the synthesis of SV40 [Simian virus-40] nonvirion (tumor) and virion antigens in BS-C-1 cells. The drug was effective before or at any stage after addition of the virus as long as synthesis of these antigens was still in progress. Removal of the drug, even after several days of contact with the cells, promptly resulted in replication of the virus. This drug was also effective against an RNA virus, poliovirus type 1. Exposure of the cells to chloramphenicol at 50 [mu]g/ ml for 5 days before and after addition of SV40 virus failed to inhibit synthesis of the tumor and virion antigens but did inhibit the cytopathic effect of the virus. Despite the marked cellular toxicity of dactinomycin at 1 [mu]g/ml, there was only partial reduction in the amount of tumor and virion antigens synthesized.