Physical and antibiotic stresses require activation of the RsbU phosphatase to induce the general stress response in Listeria monocytogenes.
Physical and antibiotic stresses require activation of the RsbU phosphatase to induce the general stress response in Listeria monocytogenes.
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DOI：
10.1099/mic.0.041202-0
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发表时间：
2010-09
期刊：
影响因子：
--
通讯作者：
Price CW
中科院分区：
文献类型：
--
作者：
Shin JH;Brody MS;Price CW
在单核细胞增生李斯特菌的致病性菌株中，σB转录因子在食源性感染的结果中具有关键作用。该因子被各种应激激活，以提供针对多种挑战的一般保护，包括在胃肠道通过期间遇到的挑战。它还与PrfA调节因子一起作用，以控制进入肠腔细胞所需的毒力基因。环境和营养信号通过一个网络调节σB活性，该网络由伴侣转换机制运作，其中蛋白质相互作用由丝氨酸磷酸化控制。该网络在相关细菌枯草芽孢杆菌中得到了很好的表征。李斯特菌的一个关键区别是只存在一种输入磷酸酶RsbU，而不是B中发现的两种。枯草杆菌。在这里，我们的目标是确定这种唯一的磷酸酶是否需要传递物理，抗生素和营养应激信号，或者是否存在其他途径。为此，我们构造了L。在一些实施方案中，使用携带单拷贝、σ B依赖性opuCA-lacZ报告基因融合体的单核细胞增多症10403 S菌株来测定rsbU缺失在生理条件下的影响。所有测试的胁迫，包括酸、抗生素、冷、乙醇、热、渗透压和营养挑战，都需要RsbU来激活σB。这对于冷应激激活具有特别重要的意义，冷应激激活在B中通过磷酸酶非依赖性机制发生。枯草杆菌。我们还测定了激活RsbU的上游RsbT调节子中D80 N取代的影响。该突变体具有与低的和不可诱导的磷酸酶活性一致的表型，但仍然对营养胁迫作出反应。我们推断，RsbU活性，而不是其诱导所需的营养信号，这将进入网络下游的RsbU。
Among pathogenic strains of Listeria monocytogenes, the σB transcription factor has a pivotal role in the outcome of food-borne infections. This factor is activated by diverse stresses to provide general protection against multiple challenges, including those encountered during gastrointestinal passage. It also acts with the PrfA regulator to control virulence genes needed for entry into intestinal lumen cells. Environmental and nutritional signals modulate σB activity via a network that operates by the partner switching mechanism, in which protein interactions are controlled by serine phosphorylation. This network is well characterized in the related bacterium Bacillus subtilis. A key difference in Listeria is the presence of only one input phosphatase, RsbU, instead of the two found in B. subtilis. Here, we aim to determine whether this sole phosphatase is required to convey physical, antibiotic and nutritional stress signals, or if additional pathways might exist. To that end, we constructed L. monocytogenes 10403S strains bearing single-copy, σB-dependent opuCA–lacZ reporter fusions to determine the effects of an rsbU deletion under physiological conditions. All stresses tested, including acid, antibiotic, cold, ethanol, heat, osmotic and nutritional challenge, required RsbU to activate σB. This was of particular significance for cold stress activation, which occurs via a phosphatase-independent mechanism in B. subtilis. We also assayed the effects of the D80N substitution in the upstream RsbT regulator that activates RsbU. The mutant had a phenotype consistent with low and uninducible phosphatase activity, but nonetheless responded to nutritional stress. We infer that RsbU activity but not its induction is required for nutritional signalling, which would enter the network downstream from RsbU.
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影响因子：
3.6
作者：
Brody, Margaret S.;Stewart, Valley;Price, Chester W.
通讯作者：
Price, Chester W.
影响因子：
3.2
作者：
Gaidenko, Tatiana A.;Kim, Tae-Jong;Price, Chester W.
通讯作者：
Price, Chester W.
影响因子：
3.2
作者：
Becker, LA;Çetin, MS;Benson, AK
通讯作者：
Benson, AK
影响因子：
3.2
作者：
Delumeau, O;Lewis, RJ;Yudkin, MD
通讯作者：
Yudkin, MD
影响因子：
2.1
作者：
Eymann, C;Hecker, M
通讯作者：
Hecker, M