A Listeria monocytogenes RNA Helicase Essential for Growth and Ribosomal Maturation at Low Temperatures Uses Its C Terminus for Appropriate Interaction with the Ribosome
A Listeria monocytogenes RNA Helicase Essential for Growth and Ribosomal Maturation at Low Temperatures Uses Its C Terminus for Appropriate Interaction with the Ribosome
复制标题
单核细胞增生李斯特氏菌 RNA 解旋酶对于低温下生长和核糖体成熟至关重要，利用其 C 末端与核糖体进行适当的相互作用
DOI：
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发表时间：
2012
影响因子：
3.2
通讯作者：
J. Johansson
中科院分区：
文献类型：
--
作者：
Sakura Netterling;K. Vaitkevicius;Stefan Nord;J. Johansson
摘要单核细胞增生李斯特菌是一种革兰氏阳性的食源性人类病原体，能够在接近0°C的温度下生长，因此受到食品工业的极大关注。在这项工作中，我们研究了一个DExD盒RNA解旋酶在单核细胞增生李斯特菌的生理作用。RNA解旋酶Lmo 1722在低温下是最佳生长所必需的，而在37°C下是不稳定的。Δ lmo 1722菌株由于flaA表达降低导致鞭毛主要亚基FlaA下调而运动性降低。通过核糖体分离实验，观察到Lmo 1722主要与核糖体的50 S亚基结合。Lmo 1722的缺失降低了50 S核糖体亚基和成熟70 S核糖体的比例，并影响了23 S前体rRNA的加工。在表达Lmo 1722的Δ lmo 1722菌株中，核糖体谱可以恢复到野生型水平。有趣的是，Lmo 1722的C-末端部分对于低温生长、运动、23 S rRNA加工和适当的核糖体成熟是多余的。然而，Lmo 1722缺乏的C末端显示出降低的50 S和70 S馏分的亲和力，这表明C末端是重要的Lmo 1722的50 S亚基的适当指导。两者合计，我们的研究结果表明，李斯特菌RNA解旋酶Lmo 1722是必不可少的生长在低温下，运动，和rRNA加工，是重要的核糖体成熟，主要与核糖体的50 S亚基。
ABSTRACT Listeria monocytogenes, a Gram-positive food-borne human pathogen, is able to grow at temperatures close to 0°C and is thus of great concern for the food industry. In this work, we investigated the physiological role of one DExD-box RNA helicase in Listeria monocytogenes. The RNA helicase Lmo1722 was required for optimal growth at low temperatures, whereas it was dispensable at 37°C. A Δlmo1722 strain was less motile due to downregulation of the major subunit of the flagellum, FlaA, caused by decreased flaA expression. By ribosomal fractionation experiments, it was observed that Lmo1722 was mainly associated with the 50S subunit of the ribosome. Absence of Lmo1722 decreased the fraction of 50S ribosomal subunits and mature 70S ribosomes and affected the processing of the 23S precursor rRNA. The ribosomal profile could be restored to wild-type levels in a Δlmo1722 strain expressing Lmo1722. Interestingly, the C-terminal part of Lmo1722 was redundant for low-temperature growth, motility, 23S rRNA processing, and appropriate ribosomal maturation. However, Lmo1722 lacking the C terminus showed a reduced affinity for the 50S and 70S fractions, suggesting that the C terminus is important for proper guidance of Lmo1722 to the 50S subunit. Taken together, our results show that the Listeria RNA helicase Lmo1722 is essential for growth at low temperatures, motility, and rRNA processing and is important for ribosomal maturation, being associated mainly with the 50S subunit of the ribosome.
DbpA（一种对 23S 核糖体 RNA 具有特异性的大肠杆菌 DEAD 蛋白）的 RNA 依赖性三磷酸腺苷酶活性的动力学分析。
DOI：
10.1021/bi981837y
发表时间：
1998
期刊：
Biochemistry.
影响因子：
--
作者：
Tsu,CA;Uhlenbeck,OC
通讯作者：
Uhlenbeck,OC
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