The effect of Escherichia coli ribosomal protein S1 on the translational specificity of bacterial ribosomes

• Published in: The Journal of biological chemistry 1989-02, Vol.264 (4), p.2228-2235
• Main Authors: Roberts, M W, Rabinowitz, J C
• Format: Article
• Language: English
• Subjects: Bacteria - genetics; Bacteria - metabolism; Biological and medical sciences; Escherichia coli; Escherichia coli - genetics; Escherichia coli - metabolism; Fundamental and applied biological sciences. Psychology; Kinetics; Molecular and cellular biology; Molecular genetics; Phylogeny; Protein Biosynthesis; Ribosomal Proteins - metabolism; Ribosomes - metabolism; RNA, Messenger - genetics; Species Specificity; Translation. Translation factors. Protein processing
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(18)94166-9

Ribosomes from Gram-negative bacteria such as Escherichia coli exhibit non-specific translation of bacterial mRNAs. That is, they are able to translate mRNAs from a variety of sources in a manner independent of the “strength” of the Shine-Dalgarno region, in contrast to ribosomes from many Gram-positive bacteria, such as Bacillus subtilis, which show specific translation in only being able to translate other Gram-positive mRNA, or mRNAs that have “strong” Shine-Dalgarno regions. There is an evolutionary correlation between the translational specificity and the absence of a protein analogous to E. coli ribosomal protein S1. The specificity observed with B. subtilis ribosomes is a function of their 30 S subunit which lacks S1; translation of Gram-negative mRNA can occur with heterologous ribosomes containing the 30 S subunit of E. coli ribosomes and the 50 S subunit of B. subtilis ribosomes. However, the addition of E. coli S1 alone to B. subtilis ribosome does not overcome their characteristic inability to translate mRNA from Gram-negative organisms. By contrast, the removal of S1 from E. coli ribosomes results in translational behavior similar to that shown by B. subtilis ribosomes in that the S1-depleted E. coli ribosomes can translate mRNA from Gram-positive sources in the absence of added S1, although addition of S1 stimulates further translation of such mRNAs by the E. coli ribosomes.