Sensitivity to Ultraviolet Light of RNA Synthesis under Different Culture Conditions in Pseudomonas effusa

Comparative studies were made on the sensitivity of the synthesis of individual ribonucleic acids (RNA) components to ultraviolet light (UV) under conditions that (A) suppressed ribosomal RNA (rRNA) synthesis and permitted preferential synthesis of messenger RNA (mRNA); (B) permitted balanced synthesis of individual RNA components; and (C) suppressed mRNA synthesis and permitted preferential synthesis of rRNA. Under condition A, mRNA synthesis was found to be much more UV-sensitive in the presence than in the absence of inducer. Under condition B, no preferential inhibition of the synthesis was observed for any one of the mRNA peaks. Synthesis of rRNA was more readily found to be UV-sensitive with the increasing molecular weight of RNA under condition C than under condition B.