Ribosomal proteins of bacterial cells: strain- and species-specificity.

Abstract

Abstract The 50 s ribosomal protein of Escherichia coli labelled with [ 3 H]lysine, and the 30 s protein labelled with [ 14 C]lysine were simultaneously analysed by carboxymethyl-cellulose column chromatography. The results of this study, together with re-analysis by polyacrylamide gel electrophoresis of chromatographically isolated proteins, revealed that the 50 and 30 s subunits which contain respectively at least 15 and 11 main protein components possess almost no common protein components. In addition to the main components several minor protein constituents were detected in both ribosomal subunits. [ 14 C]Lysine-labelled ribosomal protein of E. coli Q13 was compared with [ 3 H]lysine-labelled ribosomal protein of E. coli B by means of chromatography on a carboxymethyl cellulose column. The elution pattern of the 50 s protein was found to be indistinguishable between these two strains, while the 30 s protein of Q13 contained two components which differ chromatographically from those of strain B, the total number of components being the same in each. The same differences in the 30 s protein were found when strains K12 (W1895) and B were compared. The chromatographic comparison of the labelled ribosomal proteins of E. coli and Salmonella abony indicated that the general elution patterns were very similar to each other. Clear differences were however detected in the elution positions of several components of both the 50 s and the 30 s proteins of these two species. [ 3 H]Lysine-labelled protein from Bacillus subtilis ribosomes was compared chromatographically with [ 14 C]lysine-labelled protein from B. megaterium and B. cereus ribosomes to examine the relatedness of species in the genus Bacillus . The results reveal almost no apparent similarities of both the 50 and 30 s proteins among these species. The same situation was found in comparisons of E. coli ribosomal protein with that from several Bacillus species and Sarcina lutea .