Campylobacter jejuni dsb gene expression is regulated by iron in a Fur-dependent manner and by a translational coupling mechanism.
Campylobacter jejuni dsb gene expression is regulated by iron in a Fur-dependent manner and by a translational coupling mechanism.
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DOI：
10.1186/1471-2180-11-166
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发表时间：
2011-07-25
期刊：
影响因子：
4.2
通讯作者：
Jagusztyn-Krynicka EK
中科院分区：
文献类型：
--
作者：
Grabowska AD;Wandel MP;Łasica AM;Nesteruk M;Roszczenko P;Wyszyńska A;Godlewska R;Jagusztyn-Krynicka EK
许多细菌胞质外蛋白质通过在其半胱氨酸残基之间后结晶形成的分子内二硫键来稳定。这种蛋白质修饰在细菌发病机制中起着重要作用，并且由氧化还原蛋白的Dsb（二硫键）家族促进。这些蛋白质在周质空间中以两种平行途径起作用：氧化途径和异构化途径。空肠弯曲菌的Dsb氧化途径比实验室E. coli K-12菌株。在C. jejuni 81-176基因组中，氧化途径的dsb基因排列成三个转录单位：dsbA 2-dsbB-astA，dsbA 1和dba-dsbI。它们的转录响应于环境刺激-铁的可用性-并以毛皮依赖的方式进行调节。在一个C.空肠野生型菌株及其同基因fur突变体。电泳迁移率变动分析（EMSA）证实了所分析的基因是Fur调节子的成员，但它们中的每一个都受到不同机制的调节，并且无铁和铁络合的Fur都能够在体外与C.空肠启动子区。这项研究导致了一个新的铁和毛皮调节的启动子，驱动dsbA 1基因表达的间接方式的鉴定。此外，目前的工作文件，DsbI氧化还原酶的合成是由翻译偶联的机制控制。二级dba-dsbI mRNA结构对dsbI mRNA翻译的重要性通过估计单个dsbI基因从其自身启动子的表达来验证。目前的研究表明铁浓度是dsb基因转录的一个重要因素。这些结果支持铁浓度的概念-也通过其对dsb基因表达的影响-可能控制在感染的不同阶段的胞质外蛋白质的丰度。我们的工作进一步表明，DsbI膜氧化还原酶的合成是由一个翻译偶联机制控制。dba的表达不仅对下游dsbI基因的翻译至关重要，而且所产生的Dba蛋白可能调节DsbI的活性和/或稳定性。
Many bacterial extracytoplasmic proteins are stabilized by intramolecular disulfide bridges that are formed post-translationally between their cysteine residues. This protein modification plays an important role in bacterial pathogenesis, and is facilitated by the Dsb (disulfide bond) family of the redox proteins. These proteins function in two parallel pathways in the periplasmic space: an oxidation pathway and an isomerization pathway. The Dsb oxidative pathway in Campylobacter jejuni is more complex than the one in the laboratory E. coli K-12 strain. In the C. jejuni 81-176 genome, the dsb genes of the oxidative pathway are arranged in three transcriptional units: dsbA2-dsbB-astA, dsbA1 and dba-dsbI. Their transcription responds to an environmental stimulus - iron availability - and is regulated in a Fur-dependent manner. Fur involvement in dsb gene regulation was proven by a reporter gene study in a C. jejuni wild type strain and its isogenic fur mutant. An electrophoretic mobility shift assay (EMSA) confirmed that analyzed genes are members of the Fur regulon but each of them is regulated by a disparate mechanism, and both the iron-free and the iron-complexed Fur are able to bind in vitro to the C. jejuni promoter regions. This study led to identification of a new iron- and Fur-regulated promoter that drives dsbA1 gene expression in an indirect way. Moreover, the present work documents that synthesis of DsbI oxidoreductase is controlled by the mechanism of translational coupling. The importance of a secondary dba-dsbI mRNA structure for dsbI mRNA translation was verified by estimating individual dsbI gene expression from its own promoter. The present work shows that iron concentration is a significant factor in dsb gene transcription. These results support the concept that iron concentration - also through its influence on dsb gene expression - might control the abundance of extracytoplasmic proteins during different stages of infection. Our work further shows that synthesis of the DsbI membrane oxidoreductase is controlled by a translational coupling mechanism. The dba expression is not only essential for the translation of the downstream dsbI gene, but also Dba protein that is produced might regulate the activity and/or stability of DsbI.
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影响因子：
6.7
作者：
Danielli A;Amore G;Scarlato V
通讯作者：
Scarlato V
影响因子：
3.6
作者：
Delany, I;Spohn, G;Scarlato, V
通讯作者：
Scarlato, V
影响因子：
3.2
作者：
Kalmokoff, Martin;Lanthier, Patricia;Szymanski, Christine M.
通讯作者：
Szymanski, Christine M.
DOI：
10.1073/pnas.77.12.7347
发表时间：
1980-01-01
期刊：
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA-BIOLOGICAL SCIENCES
影响因子：
--
作者：
DITTA, G;STANFIELD, S;HELINSKI, DR
通讯作者：
HELINSKI, DR
影响因子：
6.4
作者：
KORLATH, JA;OSTERHOLM, MT;ROBINSON, RA
通讯作者：
ROBINSON, RA