...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of bacteriology >Genetic Analysis of the Protein Shell of the Microcompartments Involved in Coenzyme B12-Dependent 1,2-Propanediol Degradation by Salmonella
【24h】

Genetic Analysis of the Protein Shell of the Microcompartments Involved in Coenzyme B12-Dependent 1,2-Propanediol Degradation by Salmonella

机译：沙门氏菌降解辅酶B12依赖的1,2-丙二醇的微区室蛋白外壳的遗传分析。

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

摘要

Hundreds of bacterial species use microcompartments (MCPs) to optimize metabolic pathways that have toxic or volatile intermediates. MCPs consist of a protein shell encapsulating specific metabolic enzymes. In Salmonella, an MCP is used for 1,2-propanediol utilization (Pdu MCP). The shell of this MCP is composed of eight different types of polypeptides, but their specific functions are uncertain. Here, we individually deleted the eight genes encoding the shell proteins of the Pdu MCP. The effects of each mutation on 1,2-PD degradation and MCP structure were determined by electron microscopy and growth studies. Deletion of the pduBB′, pduJ, or pduN gene severely impaired MCP formation, and the observed defects were consistent with roles as facet, edge, or vertex protein, respectively. Metabolite measurements showed that pduA, pduBB′, pduJ, or pduN deletion mutants accumulated propionaldehyde to toxic levels during 1,2-PD catabolism, indicating that the integrity of the shell was disrupted. Deletion of the pduK, pduT, or pduU gene did not substantially affect MCP structure or propionaldehyde accumulation, suggesting they are nonessential to MCP formation. However, the pduU or pduT deletion mutants grew more slowly than the wild type on 1,2-PD at saturating B12, indicating that they are needed for maximal activity of the 1,2-PD degradative enzymes encased within the MCP shell. Considering recent crystallography studies, this suggests that PduT and PduU may mediate the transport of enzyme substrates/cofactors across the MCP shell. Interestingly, a pduK deletion caused MCP aggregation, suggesting a role in the spatial organization of MCP within the cytoplasm or perhaps in segregation at cell division.
机译：数百种细菌使用微隔室（MCP）来优化具有毒性或挥发性中间体的代谢途径。 MCP由包裹特定代谢酶的蛋白质壳组成。在“沙门氏菌”中，MCP用于1,2-丙二醇的利用（Pdu MCP）。该MCP的外壳由八种不同类型的多肽组成，但其具体功能尚不确定。在这里，我们单独删除了八个编码Pdu MCP外壳蛋白的基因。通过电子显微镜和生长研究确定每种突变对1,2-PD降解和MCP结构的影响。 pduBB '， pduJ 或 pduN 基因的删除严重损害了MCP的形成，并且观察到的缺陷与小平面，边缘，或顶点蛋白。代谢物测量表明， pduA ， pduBB '， pduJ 或 pduN 缺失突变体在1期间积累了丙醛至毒性水平。 ，2-PD分解代谢，表明壳的完整性被破坏。 pduK ， pduT 或 pduU 基因的删除并没有实质性地影响MCP结构或丙醛积累，表明它们与MCP的形成无关。然而，在饱和的B 12 上， pduU 或 pduT 缺失突变体的生长比野生型慢于1,2-PD，表明它们装在MCP外壳中的1,2-PD降解酶的最大活性是必需的。考虑到最近的晶体学研究，这表明PduT和PduU可能介导酶底物/辅因子在MCP外壳上的转运。有趣的是， pduK 缺失导致MCP聚集，提示在细胞质内MCP的空间组织或细胞分裂中的分离中起作用。

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