Isolation and properties of an RNA fraction present inBrucellaculture supernatants

Abstract

The supernatant fluids of batch and continuous cultures of Brucella strains contained up to 100 mg/l of soluble RNA which could be recovered by precipitation with lysozyme, This RNA fraction had many of the properties of ribosomal RNA and was single-stranded, sensitive to ribonuclease, with an approximate sedimentation constant of 5S, a molecular weight of about 35000 daltons and an adenine; guanine; cytosine; uracil content of 17.5; 26.5; 33; 23 mol% respectively. RNA fractions from lysozyme precipitates evoked high titres of Brucella agglutinins on injection into rabbits and induced acute inflammatory responses in guinea-pig skin. Highly purified RNA fractions prepared by phenol extraction of lysozyme precipitates did not evoke antibodies to Brucella abortus.

Release of 5'-Guanosine Monophosphate and Adenine by Brucella abortus and Their Role in the Intracellular Survival of the Bacteria

“…Their study indicated that nucleotides are converted to nucleosides through the action of a cell-associated 5'-nucleotidase and that it is the nucleoside that is responsible for the inhibition. Corbel and Brewer [4] have shown that supernatant fluids from continuous cultures of Brucella contain up to 100 mg of soluble RNA/liter.…”