• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>MicrobiologyOpen >Zinc coordination is essential for the function and activity of the type II secretion ATPase EpsE
【24h】

Zinc coordination is essential for the function and activity of the type II secretion ATPase EpsE

机译：锌配位对于II型分泌ATPase EpsE的功能和活性至关重要

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Abstract The type II secretion system Eps in Vibrio cholerae promotes the extracellular transport of cholera toxin and several hydrolytic enzymes and is a major virulence system in many Gram-negative pathogens which is structurally related to the type IV pilus system. The cytoplasmic ATPase EpsE provides the energy for exoprotein secretion through ATP hydrolysis. EpsE contains a unique metal-binding domain that coordinates zinc through a tetracysteine motif (CXXCX 29 CXXC), which is also present in type IV pilus assembly but not retraction ATPases. Deletion of the entire domain or substitution of any of the cysteine residues that coordinate zinc completely abrogates secretion in an EpsE-deficient strain and has a dominant negative effect on secretion in the presence of wild-type EpsE. Consistent with the in vivo data, chemical depletion of zinc from purified EpsE hexamers results in loss of in vitro ATPase activity. In contrast, exchanging the residues between the two dicysteines with those from the homologous ATPase XcpR from Pseudomonas aeruginosa does not have a significant impact on EpsE. These results indicate that, although the individual residues in the metal-binding domain are generally interchangeable, zinc coordination is essential for the activity and function of EpsE.
机译：摘要霍乱弧菌的II型分泌系统Eps促进霍乱毒素和几种水解酶的细胞外转运，是许多革兰氏阴性病原体的主要毒力系统，在结构上与IV型菌毛系统有关。细胞质ATPase EpsE通过ATP水解为外蛋白分泌提供能量。 EpsE包含一个独特的金属结合结构域，该结构域通过四半胱氨酸基序（CXXCX 29 CXXC）协调锌，该基团也存在于IV型菌毛组装中，但不存在回缩ATPase。完整的结构域的缺失或配位锌的任何半胱氨酸残基的取代完全消除了EpsE缺陷菌株中的分泌，并且在存在野生型EpsE时对分泌具有显着的负面影响。与体内数据一致，纯化的EpsE六聚体中锌的化学消耗导致体外ATPase活性降低。相反，将两个双半胱氨酸之间的残基与铜绿假单胞菌的同源ATPase XcpR的残基交换不会对EpsE产生重大影响。这些结果表明，尽管金属结合域中的各个残基通常是可互换的，但是锌配位对于EpsE的活性和功能至关重要。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号