...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Biochemistry >A highly active, soluble mutant of the membrane-associated (S)-mandelate dehydrogenase from Pseudomonas putida.
【24h】

A highly active, soluble mutant of the membrane-associated (S)-mandelate dehydrogenase from Pseudomonas putida.

机译：恶臭假单胞菌的膜相关（S）-扁桃酸脱氢酶的高活性，可溶性突变体。

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

(S)-Mandelate dehydrogenase (MDH) from Pseudomonas putida, a member of the flavin mononucleotide-dependent alpha-hydroxy acid oxidase/dehydrogenase family, is a membrane-associated protein, in contrast to the more well-characterized members of this protein family including glycolate oxidase (GOX) from spinach. In a previous study [Mitra, B., et al. (1993) Biochemistry 32, 12959-12967], the membrane association of MDH was correlated to a 53 amino acid segment in the interior of the primary sequence by construction of a chimeric enzyme, MDH-GOX1, in which the membrane-binding segment in MDH was deleted and replaced with the corresponding 34 amino acid segment from the soluble GOX. Though MDH-GOX1 was soluble, it was an inefficient, nonspecific enzyme that involved a different transition state for the catalyzed reaction from that of the wild-type MDH. In the present study, it is shown that the membrane-binding segment in MDH is somewhat shorter, approximately 39 residues long. Partial or total deletion of this segment disrupts membrane localization of MDH. This segment is not important for substrate oxidation activity. A new chimera, MDH-GOX2, was created by replacing this shorter membrane-binding segment from MDH with the corresponding 20 amino acid segment from GOX. The soluble MDH-GOX2 is very similar to the wild-type membrane-bound enzyme in its spectroscopic properties, substrate specificity, catalytic activity, kinetic mechanism, and lack of reactivity toward oxygen. Therefore, it should prove to be a highly useful model for structural studies of MDH.
机译：与黄素单核苷酸相关的α-羟酸氧化酶/脱氢酶家族成员之一的恶臭假单胞菌的（S）-扁桃酸脱氢酶（MDH）是一种与膜相关的蛋白质，与此相比，该蛋白质家族的成员特征更为丰富包括菠菜中的乙醇酸氧化酶（GOX）。在先前的研究中[Mitra，B.等。 （1993）Biochemistry 32，12959-12967]，通过构建嵌合酶MDH-GOX1，MDH的膜缔合与一级序列内部的53个氨基酸区段相关，其中膜结合区段位于删除MDH，并用可溶性GOX中相应的34个氨基酸区段代替。尽管MDH-GOX1是可溶的，但它是一种无效的非特异性酶，与野生型MDH相比，涉及的催化反应过渡态不同。在本研究中，表明MDH中的膜结合片段略短，大约39个残基长。该片段的部分或全部缺失破坏了MDH的膜定位。该片段对于底物氧化活性并不重要。通过将来自MDH的较短的膜结合片段替换为来自GOX的相应20个氨基酸片段，创建了一个新的嵌合体MDH-GOX2。可溶性MDH-GOX2在光谱性质，底物特异性，催化活性，动力学机理和对氧气缺乏反应性方面与野生型膜结合酶非常相似。因此，它应该被证明是用于MDH结构研究的非常有用的模型。

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