[Vitamin U and RNA metabolism in prokaryotes]

The paper is concerned with a study of the vitamin U effect on the rate of 14C-uridine incorporation into various categories of RNA in E. coli MRE-600 cells. It is found that cells grown with vitamin U (0.06 mg/ml) and incubated with 14C-uridine for 5 min are able to produce a 10-12-fold increase of the label incorporation into 4 S and 5 S RNA and a 14-fold increase into high polymeric RNA in comparison with the control cells. Under longer intervals of incubation (20 min) the intensity of high-polymeric RNA formation was half as high as for 4 S and 5 S RNA formation. MAK column chromatography of high-polymeric RNA in salt and temperature gradients showed the presence of the RNA temperature fraction in bacteria cells. Vitamin U stimulates the formation of various categories of RNA and causes a quantitative increase in the RNA temperature fraction.