• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Molecular Biology >Structural and Mechanistic Insights into Caffeine Degradation by the Bacterial N-Demethylase Complex
【24h】

Structural and Mechanistic Insights into Caffeine Degradation by the Bacterial N-Demethylase Complex

机译：细菌N-脱甲基酶复合物的结构和机械洞察咖啡因降解

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Caffeine, found in many foods, beverages, and pharmaceuticals, is the most used chemical compound for mental alertness. It is originally a natural product of plants and exists widely in environmental soil. Some bacteria, such as Pseudomonas putida CBB5, utilize caffeine as a sole carbon and nitrogen source by degrading it through sequential N-demethylation catalyzed by five enzymes (NdmA, NdmB, NdmC, NdmD, and NdmE). The environmentally friendly enzymatic reaction products, methylxanthines, are high-value biochemicals that are used in the pharmaceutical and cosmetic industries. However, the structures and biochemical properties of bacterial N-demethylases remain largely unknown. Here, we report the structures of NdmA and NdmB, the initial N-1- and N-3-specific demethylases, respectively. Reverse-oriented substrate bindings were observed in the substrate-complexed structures, offering methyl position specificity for proper N-demethylation. For efficient sequential degradation of caffeine, these enzymes form a unique heterocomplex with 3:3 stoichiometry, which was confirmed by enzymatic assays, fluorescent labeling, and small-angle x-ray scattering. The binary structure of NdmA with the ferredoxin domain of NdmD, which is the first structural information for the plant-type ferredoxin domain in a complex state, was also determined to better understand electron transport during N-demethylation. These findings broaden our understanding of the caffeine degradation mechanism by bacterial enzymes and will enable their use for industrial applications. (C) 2019 Elsevier Ltd. All rights reserved.
机译：在许多食物，饮料和药物中发现的咖啡因是精神警觉的最常用的化合物。它最初是植物的天然产物，在环境土壤中广泛存在。一些细菌，例如假单胞菌普韦达CBB5，通过通过五种酶（NDMA，NDMB，NDMC，NDMD和NDME）催化的顺序N-去甲基化利用咖啡因作为唯一碳和氮源。环保酶促反应产物甲基黄嘌呤是在制药和化妆品行业中使用的高价值生化。然而，细菌N-去甲基酶的结构和生化特性仍然很大程度上是未知的。在这里，我们报告了NDMA和NDMB的结构，分别分别是初始N-1-和N-3特异性去甲基酶。在基材络合的结构中观察到逆向底物结合，为适当的N-去甲基化提供甲基位置特异性。为了有效顺序降解咖啡因，这些酶形成具有3：3化学计量的独特杂蛋白，通过酶测定，荧光标记和小角X射线散射证实。 NDMA与NDMD的富铁素域的二元结构，其是植物型富勒沙霉蛋白结构域在复杂状态下的第一结构信息，也决定以在N-去甲基化期间更好地理解电子传输。这些调查结果深化了细菌酶对咖啡因降解机制的理解，并可用于工业应用。 （c）2019 Elsevier Ltd.保留所有权利。

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