EXCRETION AND DEGRADATION OF RIBONUCLEIC ACID BY BACILLUS SUBTILIS.

Demain, A. L. (Merck & Co., Inc., Rahway, N.J.), R. W. Burg, and D. Hendlin. Excretion and degradation of ribonucleic acid by Bacillus subtilis. J. Bacteriol. 89:640-646. 1965.-Bacillus subtilis MB-1480 was found to produce several 5'-ribonucleotides in the extracellular medium, in addition to the previously found 5'-guanosine monophosphate and guanosine diphosphate. The nucleotides accumulated after excretion of high-molecular-weight ribonucleic acid (RNA) and subsequent extracellular breakdown. Excretion of RNA paralleled growth closely, and was accompanied by deoxyribonucleic acid (DNA) and protein excretion. The process occurred in the absence of visible lysis. Whereas extracellular DNA was stable, the other macromolecules were degraded after excretion. With extracellular DNA as a measure of maximal lysis, it was calculated that the major part of the extracellular RNA must have been excreted by cells which had not undergone lysis.