The mxd operon in Shewanella oneidensis MR-1 is induced in response to starvation and regulated by ArcS/ArcA and BarA/UvrY.
The mxd operon in Shewanella oneidensis MR-1 is induced in response to starvation and regulated by ArcS/ArcA and BarA/UvrY.
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DOI：
10.1186/1471-2180-13-119
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发表时间：
2013-05-27
期刊：
影响因子：
4.2
通讯作者：
Spormann AM
中科院分区：
文献类型：
--
作者：
Müller J;Shukla S;Jost KA;Spormann AM
S. oneidensis MR-1是一种异化金属还原菌。在缺氧条件下S. oneidensis MR-1附着并使用不溶性矿物质如Fe（III）和Mn（IV）氧化物作为电子受体。在实验室中，S. oneidensis MR-1在流体动力学流动条件下在硼硅酸盐玻璃表面上形成生物膜;先前发现生物膜的形成依赖于mxd基因簇（mxdABCD）。本研究揭示了环境和遗传因素对S.单齿菌MR-1。生理实验用S.携带与mxd启动子的转录lacZ融合的oneidensis MR-1菌株鉴定了电子供体饥饿作为诱导mxd基因表达的关键因素。Tn 5突变鉴定了ArcS/ArcA双组分信号系统作为S. oneidensis MR-1在低渗条件下的生长。携带与mxd启动子融合的转录gfp -报告基因的p53 arcS和p53 arcA菌株的生物膜揭示了mxd表达的降低，表明ArcS/ArcA对于在生物膜条件下激活mxd表达是必需的。生物膜的mixarcS和mixarcA突变体不能形成一个紧凑的三维结构与低水平的mxd表达一致。此外，BarA/UvrY被鉴定为在缺氧条件下mxd表达的主要调节因子。有趣的是，BisbarA和BisuvrY突变体的生物膜能够形成三维结构，然而，与野生型生物膜相比，三维结构不那么紧凑。我们在这里已经表明，在S. oneidensis MR-1在转录上响应于碳饥饿并由ArcS/ArcA和BarA/UvrY信号系统控制。BarA可能作为一个传感器来评估细胞的代谢状态，包括碳饥饿，导致mxd操纵子的表达，从而控制生物膜的形成。
S. oneidensis MR-1 is a dissimilatory metal-reducing bacterium. Under anoxic conditions S. oneidensis MR-1 attaches to and uses insoluble minerals such as Fe(III) and Mn(IV) oxides as electron acceptors. In the laboratory, S. oneidensis MR-1 forms biofilms under hydrodynamic flow conditions on a borosilicate glass surface; formation of biofilms was previously found to be dependent on the mxd gene cluster (mxdABCD). This study revealed environmental and genetic factors regulating expression of the mxd genes in S. oneidensis MR-1. Physiological experiments conducted with a S. oneidensis MR-1 strain carrying a transcriptional lacZ fusion to the mxd promoter identified electron donor starvation as a key factor inducing mxd gene expression. Tn5 mutagenesis identified the ArcS/ArcA two-component signaling system as a repressor of mxd expression in S. oneidensis MR-1 under planktonic conditions. Biofilms of ∆arcS and ∆arcA strains carrying a transcriptional gfp -reporter fused to the mxd promoter revealed a reduced mxd expression, suggesting that ArcS/ArcA are necessary for activation of mxd expression under biofilm conditions. Biofilms of ∆arcS and ∆arcA mutants were unable to form a compact three-dimensional structure consistent with a low level of mxd expression. In addition, BarA/UvrY was identified as a major regulator of mxd expression under planktonic conditions. Interestingly, biofilms of ∆barA and ∆uvrY mutants were able to form three-dimensional structures that were, however, less compact compared to wild type biofilms. We have shown here that the mxd genes in S. oneidensis MR-1 are controlled transcriptionally in response to carbon starvation and by the ArcS/ArcA and the BarA/UvrY signaling system. BarA might function as a sensor to assess the metabolic state of the cell, including carbon starvation, leading to expression of the mxd operon and therefore control biofilm formation.
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影响因子：
4.4
作者：
Gao H;Wang X;Yang ZK;Palzkill T;Zhou J
通讯作者：
Zhou J
DOI：
10.1073/pnas.0403064101
发表时间：
2004-09-07
影响因子：
11.1
作者：
Malpica, R;Franco, B;Georgellis, D
通讯作者：
Georgellis, D
影响因子：
3.6
作者：
Gralnick, JA;Brown, CT;Newman, DK
通讯作者：
Newman, DK
DOI：
10.1073/pnas.85.6.1888
发表时间：
1988-03-01
影响因子：
11.1
作者：
IUCHI, S;LIN, ECC
通讯作者：
LIN, ECC
影响因子：
3.2
作者：
Henke, JM;Bassler, BL
通讯作者：
Bassler, BL