The effects of disruptions in ribosomal active sites and in intersubunit contacts on ribosomal degradation in Escherichia coli
The effects of disruptions in ribosomal active sites and in intersubunit contacts on ribosomal degradation in Escherichia coli
复制标题
核糖体活性位点和亚基间接触的破坏对大肠杆菌核糖体降解的影响
作者：
Anton Paier;Margus Leppik;A. Soosaar;T. Tenson;Ü. Maiväli
虽然核糖体在大多数条件下非常稳定，但核糖体降解确实发生在不同的生物群体中，以响应特定的压力或环境条件。虽然酵母中的非功能性核糖体衰变（NRD）被很好地表征，但对细菌中启动核糖体降解的机制知之甚少。在这里，我们测试核糖体降解生长大肠杆菌表达突变体核糖体。我们发现16S rRNA解码中心（G530U和A1492C）和23S rRNA活性位点（A2451G）的突变不会导致核糖体降解。相反，23S rRNA突变U2585A引起E.杆菌我们进一步测试了23S rRNA中的突变，这些突变破坏了核糖体亚基间桥B2a和B3。23S rRNA的螺旋69的缺失和同一螺旋中的点突变A1912 G不会使核糖体不稳定，而H69中的突变A1919 G和H71中的突变A1960 G的表达导致突变体和野生型核糖体的降解。我们的研究结果表明，在大肠杆菌中，核糖体降解是一种主动诱导的机制，需要从头蛋白质合成。大肠杆菌，它同时降解结构上无活性和活性的核糖体。
Although ribosomes are very stable under most conditions, ribosomal degradation does occur in diverse groups of organisms in response to specific stresses or environmental conditions. While non-functional ribosome decay (NRD) in yeast is well characterized, very little is known of the mechanisms that initiate ribosomal degradation in bacteria. Here we test ribosome degradation in growing Escherichia coli expressing mutant ribosomes. We found that mutations in the 16S rRNA decoding centre (G530U and A1492C) and 23S rRNA active site (A2451G) do not lead to ribosomal degradation. In contrast, 23S rRNA mutation U2585A causes degradation of both the large and small ribosomal subunits in E. coli. We further tested mutations in 23S rRNA, which disrupt ribosomal intersubunit bridges B2a and B3. Deletion of helix 69 of 23S rRNA and the point mutation A1912G in the same helix did not destabilize ribosomes, while expression of mutations A1919G in H69 and A1960G in H71 led to degradation of both mutant and wild-type ribosomes. Our results suggest an actively induced mechanism requiring de novo protein synthesis for ribosomal degradation in E. coli, which degrades both structurally inactive and active ribosomes.
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影响因子：
16
作者：
LaRiviere, Frederick J.;Cole, Sarah E.;Moore, Melissa J.
通讯作者：
Moore, Melissa J.
对大肠杆菌质粒衍生的 16S 核糖体 RNA 进行等位基因特异性结构探测。
影响因子：
3.5
作者：
Powers,T;Noller,HF
通讯作者：
Noller,HF
DOI：
10.1002/jss.400020210
发表时间：
1974-01-01
期刊：
Journal of Supramolecular Structure
影响因子：
--
作者：
NOMURA M
通讯作者：
NOMURA M
影响因子：
16
作者：
Jacob, Asha Ivy;Koehrer, Caroline;Davies, Bryan William;RajBhandary, Uttam Lal;Walker, Graham Charles
通讯作者：
Walker, Graham Charles