• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Applied Microbiology >Degradation of Granular Starch by the Bacterium Microbacterium aurum Strain B8.A Involves a Modular α-Amylase Enzyme System with FNIII and CBM25 Domains
【24h】

Degradation of Granular Starch by the Bacterium Microbacterium aurum Strain B8.A Involves a Modular α-Amylase Enzyme System with FNIII and CBM25 Domains

机译：金黄色细菌细菌菌株B8.A对颗粒淀粉的降解涉及具有FNIII和CBM25结构域的模块化α-淀粉酶系统

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

摘要

The bacterium Microbacterium aurum strain B8.A, originally isolated from a potato plant wastewater facility, is able to degrade different types of starch granules. Here we report the characterization of an unusually large, multidomain M. aurum B8.A α-amylase enzyme (MaAmyA). MaAmyA is a 1,417-amino-acid (aa) protein with a predicted molecular mass of 148 kDa. Sequence analysis of MaAmyA showed that its catalytic core is a family GH13_32 α-amylase with the typical ABC domain structure, followed by a fibronectin (FNIII) domain, two carbohydrate binding modules (CBM25), and another three FNIII domains. Recombinant expression and purification yielded an enzyme with the ability to degrade wheat and potato starch granules by introducing pores. Characterization of various truncated mutants of MaAmyA revealed a direct relationship between the presence of CBM25 domains and the ability of MaAmyA to form pores in starch granules, while the FNIII domains most likely function as stable linkers. At the C terminus, MaAmyA carries a 300-aa domain which is uniquely associated with large multidomain amylases; its function remains to be elucidated. We concluded that M. aurum B8.A employs a multidomain enzyme system to initiate degradation of starch granules via pore formation.
机译：最初从马铃薯工厂废水处理设施中分离出的金黄色微细菌菌株B8.A能够降解不同类型的淀粉颗粒。在这里，我们报告一个异常大的，多域金黄色葡萄球菌B8.Aα​​-淀粉酶（MaAmyA）的表征。 MaAmyA是一种1,417个氨基酸（aa）的蛋白质，预测的分子量为148 kDa。 MaAmyA的序列分析表明，它的催化核心是具有典型ABC结构域结构的GH13_32α-淀粉酶家族，其后是纤连蛋白（FNIII）结构域，两个碳水化合物结合模块（CBM25）和另外三个FNIII结构域。重组表达和纯化产生的酶具有通过引入孔降解小麦和马铃薯淀粉颗粒的能力。 MaAmyA的各种截断突变体的表征揭示了CBM25结构域的存在与MaAmyA在淀粉颗粒中形成孔的能力之间的直接关系，而FNIII结构域最有可能充当稳定的接头。在C末端，MaAmyA带有一个300-aa结构域，该结构域与大型多域淀粉酶唯一相关;其功能仍有待阐明。我们得出的结论是，金黄色葡萄球菌B8.A使用多域酶系统通过孔形成引发淀粉颗粒的降解。

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