...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of enzyme inhibition and medicinal chemistry. >An overview of the alpha-, beta- and gamma-carbonic anhydrases from Bacteria : can bacterial carbonic anhydrases shed new light on evolution of bacteria?
【24h】

An overview of the alpha-, beta- and gamma-carbonic anhydrases from Bacteria : can bacterial carbonic anhydrases shed new light on evolution of bacteria?

机译：细菌的α，β和γ碳酸酐酶概述：细菌碳酸酐酶能否为细菌的进化提供新的思路？

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

摘要

Carbonic anhydrases (CAs, EC 4.2.1.1) are metalloenzymes which catalyze a simple but physiologically crucial reaction in all life Domains, the carbon dioxide hydration to bicarbonate and protons: CO2?+?H2O ? ?+?H+. These enzymes are involved in many physiologic processes, such as photosynthesis, respiration, CO2 transport, as well as metabolism of xenobiotics. Five different, genetically distinct CA families are known to date: the α-, β-, γ-, δ- and ζ-CAs. α-, β- and δ-CAs use Zn(II) ions at the active site, the γ-CAs are probably Fe(II) enzymes (but they are active also with bound Zn(II) or Co(II) ions), whereas the ζ-class uses Cd(II) or Zn(II) to perform the physiologic reaction catalysis. Bacteria encode for enzymes belonging to the α-, β-, and γ-CA classes. They contain zinc ion (Zn2+) in their active site, coordinated by three histidine residues and a water molecule/hydroxide ion (in the α and γ) or by two cysteine and one histidine residues (in the β class), with the fourth ligand being a water molecule/hydroxide ion. Here we propose that bacterial CAs can be used as markers for understanding the evolution and genetic variability of the Gram-positive and Gram-negative bacteria. We addressed several questions such as: (1) why are α-CAs present only in the genome of Gram-negative bacteria; (2) why are α-CAs not present in all Gram-negative bacteria; (3) why do Bacteria show an intricate pattern of CA gene expression; (4) what are the physiologic roles of such diverse CAs in these prokaryotes. We proposed possible answers to the previous questions. Moreover, we speculated on the evolution of the CA classes (α, β and γ) identified in the Gram-negative and -positive bacteria. Our main hypothesis is that from the ancestral Ur-CA, the γ-class arose first, followed by the β-class; the α-class CAs came last it is found only in the Gram-negative bacteria.
机译：碳酸酐酶（CAs，EC 4.2.1.1）是金属酶，可催化所有生命域中简单但对生理至关重要的反应，即二氧化碳水合成碳酸氢盐和质子：CO 2 ？+？H 2 O？ ？ +？H + 。这些酶参与许多生理过程，例如光合作用，呼吸作用，CO 2 转运以及异种生物的代谢。迄今为止已知五个不同的，遗传上不同的CA家族：α-，β-，γ-，δ-和ζ-CA。 α-，β-和δ-CAs在活性位点使用Zn（II）离子，γ-CAs可能是Fe（II）酶（但它们也对结合的Zn（II）或Co（II）离子有活性） ，而ζ类使用Cd（II）或Zn（II）进行生理反应催化。细菌编码属于α-，β-和γ-CA类的酶。它们的活性位点含有锌离子（Zn 2 + ），由三个组氨酸残基和一个水分子/氢氧根离子（分别在α和γ中）或两个半胱氨酸和一个组氨酸残基（在其中β类），而第四种配体是水分子/氢氧根离子。在这里，我们建议细菌CAs可以用作了解革兰氏阳性和革兰氏阴性细菌的进化和遗传变异性的标记。我们解决了几个问题，例如：（1）为什么仅在革兰氏阴性细菌的基因组中存在α-CA？ （2）为什么所有革兰氏阴性菌中都不存在α-CAs？ （3）为什么细菌显示出复杂的CA基因表达模式？ （4）在这些原核生物中，这些不同的CA的生理作用是什么。我们对先前的问题提出了可能的答案。此外，我们推测了革兰氏阴性菌和阳性菌中CA类（α，β和γ）的进化。我们的主要假设是，从祖先的Ur-CA开始，首先出现γ类，然后是β类。 α级CA排在最后，仅在革兰氏阴性细菌中发现。

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