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Magnesium ion-independent ribonucleic acid depolymerases in bacteria.

H E Wade·H K Robinson
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Abstract

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.

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ArthrobacterCorynebacteriumEnterobacterEscherichia coliFlavobacteriumHydrogen-Ion ConcentrationMagnesiumMicrococcusProteusPseudomonasRNA, BacterialRhizobiumRibonucleasesXanthomonasJournal Article

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H E Wade, H K Robinson. 1966. Magnesium ion-independent ribonucleic acid depolymerases in bacteria.. https://doi.org/10.1042/bj1010467

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