Altered polyamine concentrations in cytomegalovirus-infected human cells

Polyamines have a regulatory effect on DNA and RNA synthesis and their levels are elevated in rapidly growing cells, including lymphoblasts. However, as shown in the current experiments, exposure to cytomegalovirus (CMV) reduces the polyamine levels in these cells, suggesting that the virus interferes with their metabolism. Studies have shown that the activity of ornithine decarboxylase is increased in CMV-infected fibroblasts and that there is an increased conversion of putrescine to spermidine and spermine. Thus it may be expected that the concentration of these molecules would increase in the infected cell. However, the results presented here demonstrate that only the concentrations of putrescine and spermidine are increased, the spermine concentration decreasing with infection.