...
首页> 外文期刊>Environmental Science & Technology >Combined C and Cl Isotope Effects Indicate Differences between Corrinoids and Enzyme (Sulfurospirillum multivorans PceA) in Reductive Dehalogenation of Tetrachloroethene, But Not Trichloroethene
【24h】

Combined C and Cl Isotope Effects Indicate Differences between Corrinoids and Enzyme (Sulfurospirillum multivorans PceA) in Reductive Dehalogenation of Tetrachloroethene, But Not Trichloroethene

机译:C和Cl同位素联合作用表明在四氯乙烯而不是三氯乙烯的还原脱卤中类固醇和酶之间的差异(Sulfurospirillum multivorans PceA)

获取原文
获取原文并翻译 | 示例
           

摘要

The role of the corrinoid cofactor in reductive dehalogenation catalysis by tetrachloroethene reductive dehalogenase (PceA) of Sulfurospirillum multivorans was investigated using isotope analysis of carbon and chlorine. Crude extracts containing PceA-harboring either a native norpseudo-B_(12) or the alternative nor-B_(12) cofactor-were applied for dehalogenation of tetrachloroethene (PCE) or trichloroethene (TCE), and compared to abiotic dehalogenation with the respective purified corrinoids (norpseudovitamin B_(12) and norvitamin B_(12)), as well as several commercially available cobalamins and cobinamide. Dehalogenation of TCE resulted in a similar extent of C and Cl isotope fractionation, and in similar dualelement isotope slopes (ε_C/ε_(Cl)) of 5.0-53 for PceA enzyme and 3.7-4.S for the corrinoids. Both observations support an identical reaction mechanism. For PCE, in contrast, observed C and Cl isotope fractionation was smaller in enzymatic dehalogenation, and dual-element isotope slopes (2.2-2.8) were distinctly different compared to dehalogenation mediated by corrinoids (4.6-7.0). Remarkably, ε_C/ε_(Cl) of PCE depended in addition on the corrinoid type: ε_C/ε_(Cl) values of 4.6 and 5.0 for vitamin B_(12) and norvitamin B_(12) were significantly different compared to values of 6.9 and 7.0 for norpseudovitawin B_(12) and dicyanocobinamide. Our results therefore suggest mechanistic and/or kinetic differences in catalytic PCE dehalogenation by enzymes and different corrinoids, whereas such differences were not observed for TCE.
机译:使用碳和氯的同位素分析研究了类固醇辅因子在多硫磺螺螺旋藻的四氯乙烯还原性脱卤酶(PceA)催化的还原性脱卤催化中的作用。将含有天然Norseudo-B_(12)或替代nor-B_(12)辅因子的PceA的粗提物用于四氯乙烯(PCE)或三氯乙烯(TCE)的脱卤,并与相应纯化的非生物脱卤进行比较类皮质醇(norpseudovitamin B_(12)和norvitamin B_(12))以及几种市售的钴胺素和cobinamide。 TCE的脱卤作用导致C和Cl同位素分馏程度相似,PceA酶的双元素同位素斜率(ε_C/ε_(Cl))相似,5.0-53,而类胡萝卜素的3.7-4.S。两种观察结果都支持相同的反应机制。相比之下,对于PCE,在酶促脱卤作用下观察到的C和Cl同位素分馏较小,并且双元素同位素斜率(2.2-2.8)与类胡萝卜素介导的脱卤作用(4.6-7.0)明显不同。值得注意的是,PCE的ε_C/ε_(Cl)还要取决于类胶质:维生素B_(12)和降钙素B_(12)的ε_C/ε_(Cl)值分别为4.6和5.0,而6.9和6.9的值明显不同。对于norpseudovitawin B_(12)和双氰基钴胺为7.0。因此,我们的结果表明,酶和不同类固醇在催化PCE脱卤反应中的机理和/或动力学差异,而在TCE中未观察到这种差异。

著录项

  • 来源
    《Environmental Science & Technology》 |2014年第20期|11837-11845|共9页
  • 作者单位

    Department for Isotope Biogeochemistry, Helmholtz-Centre for Environmental Research - UFZ, Permoserstrasse 15, D-04318 Leipzig, Germany;

    Department of Applied and Ecological Microbiology, Institute of Microbiology, Friedrich Schiller University, Philosophenweg 12, D-07743 Jena, Germany;

    Institute of Groundwater Ecology, Helmholtz Zentrum Muenchen, Ingolstaedter Landstrasse 1, D-85764 Neuherberg, Germany;

    Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, Ontario Canada N2L 3G1,Isotope Tracer Technologies Inc., Waterloo, Ontario Canada N2 Ⅴ 1Z5;

    Institute of Groundwater Ecology, Helmholtz Zentrum Muenchen, Ingolstaedter Landstrasse 1, D-85764 Neuherberg, Germany;

    Department of Applied and Ecological Microbiology, Institute of Microbiology, Friedrich Schiller University, Philosophenweg 12, D-07743 Jena, Germany;

    Department for Isotope Biogeochemistry, Helmholtz-Centre for Environmental Research - UFZ, Permoserstrasse 15, D-04318 Leipzig, Germany;

  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);美国《生物学医学文摘》(MEDLINE);美国《化学文摘》(CA);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
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