Electrocatalytic reduction of nitrate and selenate by NapAB.
Electrocatalytic reduction of nitrate and selenate by NapAB.
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NapAB 电催化还原硝酸盐和硒酸盐。
DOI：
10.1042/bst0390236
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发表时间：
2011
影响因子：
3.9
通讯作者：
Gates AJ
中科院分区：
文献类型：
--
作者：
Gates AJ
细菌细胞代谢以其代谢多样性和适应性而闻名。然而，某些环境带来了特殊的挑战。土壤细菌如Paracoccus pantotrophus的高还原碳底物的有氧代谢提出了这样一个挑战，因为它可能会导致过量的电子传递到呼吸氧化还原链相比，终端氧化剂，O2的可用性。在高度还原的碳底物存在下，周质泛喹啉依赖性硝酸还原酶NAP的水平上调。NAP在细胞质膜的周质面氧化泛醇并减少周质中的硝酸盐。因此，它的活性抵消了泛醇中过量还原当量的积累，从而维持泛醌/泛醇池的氧化还原平衡，而不有助于跨细胞质膜的质子动力。虽然P。pantotrophusNapAB对硝酸盐显示出高水平的底物特异性，该酶也被报道在分光光度溶液测定中还原硒酸盐。这项交易借鉴了我们目前对细菌呼吸硝酸还原酶的了解，并扩展了PFE（蛋白膜电化学）的应用，以解决和量化NapAB的硒酸还原酶活性。
Bacterial cellular metabolism is renowned for its metabolic diversity and adaptability. However, certain environments present particular challenges. Aerobic metabolism of highly reduced carbon substrates by soil bacteria such asParacoccus pantotrophuspresents one such challenge since it may result in excessive electron delivery to the respiratory redox chain when compared with the availability of terminal oxidant, O2. The level of a periplasmic ubiquinol-dependent nitrate reductase, NAP, is up-regulated in the presence of highly reduced carbon substrates. NAP oxidizes ubiquinol at the periplasmic face of the cytoplasmic membrane and reduces nitrate in the periplasm. Thus its activity counteracts the accumulation of excess reducing equivalents in ubiquinol, thereby maintaining the redox poise of the ubiquinone/ubiquinol pool without contributing to the protonmotive force across the cytoplasmic membrane. AlthoughP. pantotrophusNapAB shows a high level of substrate specificity towards nitrate, the enzyme has also been reported to reduce selenate in spectrophotometric solution assays. This transaction draws on our current knowledge concerning the bacterial respiratory nitrate reductases and extends the application of PFE (protein film electrochemistry) to resolve and quantify the selenate reductase activity of NapAB.
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影响因子：
15
作者：
Frangioni, B;Arnoux, P;Léger, C
通讯作者：
Léger, C
影响因子：
4.1
作者：
BERKS, BC;RICHARDSON, DJ;FERGUSON, SJ
通讯作者：
FERGUSON, SJ
使用直接电化学来探测硝酸还原酶周转期间的限速事件。
影响因子：
3.4
作者：
L. J. Anderson;D. Richardson;J. Butt
通讯作者：
J. Butt
影响因子：
4.1
作者：
Dridge, Elizabeth J.;Watts, Carys A.;Butler, Clive S.
通讯作者：
Butler, Clive S.
微生物还原硒酸盐和硝酸盐：常见主题和变化。
影响因子：
3.9
作者：
Carys A. Watts;Helen Ridley;E. J. Dridge;James T. Leaver;A. Reilly;David J. Richardson;C. Butler
通讯作者：
C. Butler