Department of Biochemistry and Molecular Biology, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA.
Arch Microbiol. 2012 Dec;194(12):1033-41. doi: 10.1007/s00203-012-0839-5. Epub 2012 Aug 29.
The bacterial ribosome is an important target for many antimicrobial agents. Aminoglycoside antibiotics bind to both 30S and 50S ribosomal subunits, inhibiting translation and subunit formation. During ribosomal subunit biogenesis, ribonucleases (RNases) play an important role in rRNA processing. E. coli cells deficient for specific processing RNases are predicted to have an increased sensitivity to neomycin and paromomycin. Four RNase mutant strains showed an increased growth sensitivity to both aminoglycoside antibiotics. E. coli strains deficient for the rRNA processing enzymes RNase III, RNase E, RNase G or RNase PH showed significantly reduced subunit amounts after antibiotic treatment. A substantial increase in a 16S RNA precursor molecule was observed as well. Ribosomal RNA turnover was stimulated, and an enhancement of 16S and 23S rRNA fragmentation was detected in E. coli cells deficient for these enzymes. This work indicates that bacterial RNases may be novel antimicrobial targets.
细菌核糖体是许多抗菌药物的重要靶标。氨基糖苷类抗生素与 30S 和 50S 核糖体亚基结合，抑制翻译和亚基形成。在核糖体亚基生物发生过程中，核糖核酸酶（RNase）在 rRNA 加工中发挥重要作用。预计缺乏特定加工 RNase 的大肠杆菌细胞对新霉素和巴龙霉素的敏感性增加。四种 RNase 突变株对两种氨基糖苷类抗生素的生长敏感性均增加。缺乏 rRNA 加工酶 RNase III、RNase E、RNase G 或 RNase PH 的大肠杆菌菌株在抗生素处理后亚基数量明显减少。还观察到 16S RNA 前体分子的大量增加。核糖体 RNA 周转被刺激，并且在缺乏这些酶的大肠杆菌细胞中检测到 16S 和 23S rRNA 片段的增强。这项工作表明细菌 RNase 可能是新的抗菌药物靶标。
