Identification and analysis of the osmotolerance associated genes in Listeria monocytogenes
Identification and analysis of the osmotolerance associated genes in Listeria monocytogenes
复制标题
单增李斯特菌渗透压耐受相关基因的鉴定与分析
DOI：
10.1080/02652030802056634
复制
发表时间：
2008
期刊：
影响因子：
--
通讯作者：
S. Igimi
中科院分区：
文献类型：
--
作者：
Y. Okada;S. Makino;N. Okada;H. Asakura;S. Yamamoto;S. Igimi
单核细胞增生性李斯特菌是一种具有很强耐药性的病原菌，能在恶劣的环境中生长。许多研究的机制，植物耐药性已经进行。然而，仍有许多事情是未知的。在前期的研究中，我们构建了两种L.单核细胞增生性李斯特菌EGD株的耐盐机制进行了初步研究。单核细胞增多症的分子遗传学方法。本文综述了近年来国内外学者和我们对该菌耐盐性的遗传学研究。首先，构建了转座子插入突变株，与亲本株相比，其在高渗琼脂中显示出降低的生长。克隆和序列分析结果表明，rel基因编码鸟苷四磷酸和五磷酸合成和水解蛋白，与L.单核细胞增多症。接下来，对L.使用实时聚合酶链反应（PCR）检测单核细胞增生，发现rpoN基因（替代σ因子RpoN（σ 54）编码基因）在高渗透条件下被激活。构建了rpoN缺失突变体，并分析了其对渗透胁迫的响应。在含有NaCl和肉毒碱的基本培养基中，当起始光密度高时，突变体表现出与亲本菌株的生长缺陷，尽管突变体中肉毒碱转运操纵子opuC的表达水平和肉毒碱摄取速率与EGD相似。这些结果表明，rpoN突变体可能需要更大量的肉毒碱，这可能是其在高渗透压下生长所需的。通过对这些突变体的分析，对苜蓿的耐盐性有了新的认识。单核细胞增多症。
Listeria monocytogenes, the causative agent of listeriosis, has strong osmotolerance and is able to grow in severe circumstances. Many studies of the mechanisms of listerial osmotolerance have been performed. However, there is much which remains unknown. In previous studies we constructed two kinds of mutant in L. monocytogenes EGD strain to analyse the mechanisms of osmotolerance in L. monocytogenes by molecular genetic methods. In this paper, we summarized the genetical studies of osmotolerance in this bacterium by many researchers and ourselves. First, a transposon-insertional mutant strain was constructed that showed reduced growth in high osmotic agar compared with the parental strain. The results of cloning and sequencing analysis showed that the rel gene, which encodes guanosine tetra- and pentaphosphate synthesis and hydrolysis protein, is involved in osmotolerance in L. monocytogenes. Next, the expression levels of five sigma factor coding genes in L. monocytogenes were examined using real-time polymerase chain reaction (PCR) and it was found that the rpoN gene (the alternative sigma factor RpoN (sigma54)-encoding gene) was activated under high osmotic conditions. A deletion mutant of rpoN was constructed and its response to osmotic stress was analysed. In minimal medium with NaCl and carnitine, an osmoprotectant, the mutant showed deficient growth to that of the parental strain when the starting optical density was high, though the expression level of carnitine transporter operon, opuC, and the rate of carnitine uptake in the mutant was similar to that of EGD. These results suggest that the rpoN mutant may need larger amounts of carnitine which might be needed for its growth under high osmolarity. Through the analysis of these mutants, new insights have been obtained into osmotolerance in L. monocytogenes.
绘制 sigma 54-RNA 聚合酶在 24 共有启动子元件处的相互作用。
DOI：
--
发表时间：
2003
期刊：
J. Biol. Chem. 278
影响因子：
--
作者：
Burrows;P.C.;Ishihama;A.;Buck;M.;Wigneshweraraj;S.R.
通讯作者：
S.R.
影响因子：
2.1
作者：
Okada, Yumiko;Okada, Nobuhiko;Igimi, Shizunobu
通讯作者：
Igimi, Shizunobu
DOI：
10.1016/j.ijfoodmicro.2005.02.009
发表时间：
2005-10-15
影响因子：
5.4
作者：
Makino, SI;Kawamoto, K;Igimi, S
通讯作者：
Igimi, S