Pleiotropic effect of anticapsin on HeLa S3 cells.

Anticapsin, the terminal epoxyaminoacid moiety of tetaine, inhibits irreversibly growth of HeLa S3 cells. The antibiotic decreases to a similar extent incorporation of 3H-labelled precursors into nucleic acids and protein in intact cells: inhibition of protein synthesis prevails on prolonged incubation. Also incorporation of [3H]dTTP and [3H]UTP is inhibited in the presence of anticapsin into permeabilized cells. These effects, however, are not due to the interference with DNA or RNA polymerases since anticapsin only slightly suppresses RNA polymerase activity and has no effect on DNA polymerase in the cell-free systems. The results indicate that the mechanism of antiproliferative action of anticapsin in HeLa S3 cells differs from that of tetaine and imply that inhibition of protein synthesis might be the primary effect of anticapsin.