Accumulation and Turnover of 23S Ribosomal RNA in Azithromycin-Inhibited Ribonuclease Mutant Strains of Escherichia Coli
Document Type
Article
Publication Date
10-1-2005
Description
Ribosomal RNA is normally a stable molecule in bacterial cells with negligible turnover. Antibiotics which impair ribosomal subunit assembly promote the accumulation of subunit intermediates in cells which are then degraded by ribonucleases. It is predicted that cells expressing one or more mutated ribonucleases will degrade the antibiotic-bound particle less efficiently, resulting in increased sensitivity to the antibiotic. To test this, eight ribonuclease-deficient strains of Escherichia coli were grown in the presence or absence of azithromycin. Cell viability and protein synthesis rates were decreased in these strains compared with wild type cells. Degradation of 23S rRNA and recovery from azithromycin inhibition were examined by 3H-uridine labeling and by hybridization with a 23S rRNA specific probe. Mutants defective in ribonuclease II and polynucleotide phosphorylase demonstrated hypersensitivity to the antibiotic and showed a greater extent of 23S rRNA accumulation and a slower recovery rate. The results suggest that these two ribonucleases are important in 23S rRNA turnover in antibiotic-inhibited E. coli cells.
Citation Information
Silvers, Jessica A.; and Champney, W. Scott. 2005. Accumulation and Turnover of 23S Ribosomal RNA in Azithromycin-Inhibited Ribonuclease Mutant Strains of Escherichia Coli. Archives of Microbiology. Vol.184(1). 66-77. https://doi.org/10.1007/s00203-005-0017-0 PMID: 16096836 ISSN: 0302-8933