Magnesium ion-independent ribonucleic acid depolymerases in bacteria.
The distribution of ribonucleases among bacteria has been determined from the examination of a wide variety of species. Bacteria that had been growing rapidly on a solid medium were harvested, treated with acetone and incubated in the presence of EDTA between pH4 and pH9. The ribonuclease activity was determined from the rate at which acid-soluble nucleotides were released. Out of nearly 200 strains examined, about 30 did not contain a detectable ribonuclease. The pH optima of ribonucleases in the remainder were sufficiently distinctive to suggest a use in taxonomy. Escherichia coli B was examined in more detail to determine the factors responsible for variations in the ribonuclease content of this bacterium. Growth rate had little influence on ribonuclease content when a complex medium containing no readily assimilable carbohydrate was used; the addition of glucose resulted in a marked increase in ribonuclease and a dependence of enzyme content on growth rate. An increase in the concentration of sodium chloride in the medium decreased the ribonuclease content of bacteria growing on it.
D001173:Arthrobacter / Q000201:enzymology; D003352:Corynebacterium / Q000201:enzymology; D004754:Enterobacter / Q000201:enzymology*; D004926:Escherichia coli / Q000201:enzymology*; D005417:Flavobacterium / Q000201:enzymology; D006863:Hydrogen-Ion Concentration; D008274:Magnesium; D008837:Micrococcus / Q000201:enzymology*; D011511:Proteus / Q000201:enzymology*; D011549:Pseudomonas / Q000201:enzymology*; D012329:RNA, Bacterial; D012231:Rhizobium / Q000201:enzymology; D012260:Ribonucleases / Q000378:metabolism*; D014974:Xanthomonas / Q000201:enzymology
D012329:RNA, Bacterial; D012260:Ribonucleases; D008274:Magnesium