Control of stable-RNA synthesis and maturation of 5-S RNA in Salmonella typhimurium RC str and RC rel

Abstract

1. Synthesis of stable RNA in Salmonella typhimurium RC str and RC rel during amino acid starvation was studied with the aid of methylated albumin kieselguhr chromatography and polyacrylamide gel electrophoresis. 2. Synthesis of all classes of stable RNA was coordinately controlled by the RC gene under these conditions. The effect of the RC gene therefore appears to be the same in Escherichia coli and S. typhimurium. 3. Amino acid starvation did not result in the accumulation of an abnormal form of 5-S RNA, as in E. coli. However, addition of chloramphenicol, to either starved or exponentially growing cells, did result in the accumulation of such an abnormal form, with properties very similar to those of the E. coli 5-S RNA precursor. 4. Experiments with various low doses of chloramphenicol, indicate that maturation of 5-S RNA is dependent on a minimum rate of protein synthesis, which, under our conditions, lies between 40% and 60% of the rate shown by exponentially growing cells.