The Myxococcus xanthus two-component system CorSR regulates expression of a gene cluster involved in maintaining copper tolerance during growth and development.
The Myxococcus xanthus two-component system CorSR regulates expression of a gene cluster involved in maintaining copper tolerance during growth and development.
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DOI：
10.1371/journal.pone.0068240
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发表时间：
2013
期刊：
影响因子：
3.7
通讯作者：
Muñoz-Dorado J
中科院分区：
文献类型：
--
作者：
Sánchez-Sutil MC;Pérez J;Gómez-Santos N;Shimkets LJ;Moraleda-Muñoz A;Muñoz-Dorado J
黄粘球菌（Myxococcus xanthus）是δ -变形菌门的一种生活在土壤中的成员，在饥饿时表现出复杂的发育周期。发育包括在包括金属离子浓度波动的环境中聚集和分化成具有环境抗性的黏液孢子。虽然铜是黄原分枝杆菌细胞所必需的，因为一些管家酶将其作为辅助因子，但高浓度的铜是有毒的。这些相反的作用迫使细胞维持紧密的铜稳态。大量的同源基因参与铜的解毒，所有这些基因都是差异调节的，已经在M. xanthus报道。利用框架内缺失突变体和与报告基因lacZ的融合，可以鉴定出一个双组分系统CorSR，该系统调节一个名为curA的操纵子的表达，该操纵子由9个基因组成，其表达在添加金属后缓慢增加，达到平台期。这个操纵子的转录调控是复杂的，因为转录可以在不同的启动子和不同类型的调控因子上启动。这些基因在生长发育过程中赋予铜耐受性。由于缺乏类似cbb3型细胞色素c氧化酶III亚基的基因产物的表达，与野生型菌株相比，ΔcorSR突变体在较低浓度下铜诱导类胡萝卜素的产生。这一数据可以解释为什么铜在野生型菌株的次优生长条件下而不是最佳生长条件下诱导类胡萝卜素的生物合成。
Myxococcus xanthus is a soil-dwelling member of the δ–Proteobacteria that exhibits a complex developmental cycle upon starvation. Development comprises aggregation and differentiation into environmentally resistant myxospores in an environment that includes fluctuations in metal ion concentrations. While copper is essential for M. xanthus cells because several housekeeping enzymes use it as a cofactor, high copper concentrations are toxic. These opposing effects force cells to maintain a tight copper homeostasis. A plethora of paralogous genes involved in copper detoxification, all of which are differentially regulated, have been reported in M. xanthus. The use of in-frame deletion mutants and fusions with the reporter gene lacZ has allowed the identification of a two-component system, CorSR, that modulates the expression of an operon termed curA consisting of nine genes whose expression slowly increases after metal addition, reaching a plateau. Transcriptional regulation of this operon is complex because transcription can be initiated at different promoters and by different types of regulators. These genes confer copper tolerance during growth and development. Copper induces carotenoid production in a ΔcorSR mutant at lower concentrations than with the wild-type strain due to lack of expression of a gene product resembling subunit III of cbb3-type cytochrome c oxidase. This data may explain why copper induces carotenoid biosynthesis at suboptimal rather than optimal growth conditions in wild-type strains.
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影响因子：
4.5
作者：
Gómez-Santos N;Pérez J;Sánchez-Sutil MC;Moraleda-Muñoz A;Muñoz-Dorado J
通讯作者：
Muñoz-Dorado J
影响因子：
3.6
作者：
Cho, KY;Zusman, DR
通讯作者：
Zusman, DR
影响因子：
3.6
作者：
KASHEFI, K;HARTZELL, PL
通讯作者：
HARTZELL, PL
影响因子：
2.7
作者：
HAGEN, DC;BRETSCHER, AP;KAISER, D
通讯作者：
KAISER, D
影响因子：
4.4
作者：
Moraleda-Munoz, Aurelio;Perez, Juana;Munoz-Dorado, Jose
通讯作者：
Munoz-Dorado, Jose