Dissociation of Lac messenger ribonucleic acid transcription from translation during recovery from inhibition of protein synthesis.

Studies were made of the synthesis of Lac messenger ribonucleic acid (mRNA) by Escherichia coli in the absence of protein synthesis and of the coupling of transcription of lac operon to translation. Lac mRNA was not synthesized in the presence of chloramphenicol, and its synthesis steadily decreased during K(+) deprivation and treatment with puromycin. Since under these conditions total mRNA synthesis is not inhibited it is suggested that the control of Lac mRNA is distinct from that which regulates total mRNA synthesis. Lac mRNA synthesized during recovery from K(+) starvation or from chloramphenicol inhibition is not translated into functional enzyme, suggesting translational control over beta-galactosidase synthesis.