Bacterial periplasmic nitrate and trimethylamine-N-oxide respiration coupled to menaquinol-cytochrome c reductase (Qcr): Implications for electrogenic reduction of alternative electron acceptors.
Bacterial periplasmic nitrate and trimethylamine-N-oxide respiration coupled to menaquinol-cytochrome c reductase (Qcr): Implications for electrogenic reduction of alternative electron acceptors.
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DOI：
10.1038/s41598-018-33857-2
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发表时间：
2018-10-19
影响因子：
4.6
通讯作者：
Kelly DJ
中科院分区：
文献类型：
--
作者：
Garg N;Taylor AJ;Kelly DJ
通过Nap和Tor还原酶对电子受体硝酸盐（Em +420 mV）和三甲基胺-N-氧化物（TMAO; Em +130 mV）的周质还原在革兰氏阴性细菌中广泛存在，并且通常被认为是由非能量守恒的醌醇脱氢酶驱动的。空肠弯曲杆菌可以通过硝酸盐和TMAO呼吸生长，并且先前已经假设这些电子传递的替代途径独立于在氧连接呼吸中起作用的质子动力甲基萘醌-细胞色素c还原酶复合物（QcrABC）。在这里，我们表明，qcrABC缺失突变体是完全缺乏硝酸盐和TMAO的氧限制性生长，是无法减少这些氧化剂与生理电子供体。正如预期的那样，在限氧条件下，突变体在富马酸盐上正常生长。因此，周质Nap和Tor还原酶通过C中的QcrABC接收它们的电子。jejuni，解释了Epsilonproteobacteria中NapC和TorC醌醇脱氢酶的普遍缺乏。此外，甲基喹啉（Em −75 mV）与Qcr复合物的特定使用，以驱动硝酸盐或TMAO逆着质子动力还原，使该过程成为产电的，H+/2 e −比率为2。这些结果对Qcr复合物在细菌非氧依赖性呼吸和生长中的作用具有普遍意义。
The periplasmic reduction of the electron acceptors nitrate (Em +420 mV) and trimethylamine-N-oxide (TMAO; Em +130 mV) by Nap and Tor reductases is widespread in Gram-negative bacteria and is usually considered to be driven by non-energy conserving quinol dehydrogenases. The Epsilonproteobacterium Campylobacter jejuni can grow by nitrate and TMAO respiration and it has previously been assumed that these alternative pathways of electron transport are independent of the proton-motive menaquinol-cytochrome c reductase complex (QcrABC) that functions in oxygen-linked respiration. Here, we show that a qcrABC deletion mutant is completely deficient in oxygen-limited growth on both nitrate and TMAO and is unable to reduce these oxidants with physiological electron donors. As expected, the mutant grows normally on fumarate under oxygen-limited conditions. Thus, the periplasmic Nap and Tor reductases receive their electrons via QcrABC in C. jejuni, explaining the general absence of NapC and TorC quinol dehydrogenases in Epsilonproteobacteria. Moreover, the specific use of menaquinol (Em −75 mV) coupled with a Qcr complex to drive reduction of nitrate or TMAO against the proton-motive force allows the process to be electrogenic with a H+/2e− ratio of 2. The results have general implications for the role of Qcr complexes in bacterial oxygen-independent respiration and growth.
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影响因子：
5.1
作者：
Guccione EJ;Kendall JJ;Hitchcock A;Garg N;White MA;Mulholland F;Poole RK;Kelly DJ
通讯作者：
Kelly DJ
DOI：
10.1016/0006-291x(82)91370-5
发表时间：
1982-01-01
影响因子：
3.1
作者：
ALEFOUNDER, PR;FERGUSON, SJ
通讯作者：
FERGUSON, SJ
影响因子：
3.1
作者：
Lopez, Christopher A.;Rivera-Chvez, Fabian;Baeumler, Andreas J.
通讯作者：
Baeumler, Andreas J.
影响因子：
5.1
作者：
Hein, Sascha;Witt, Samantha;Simon, Joerg
通讯作者：
Simon, Joerg
影响因子：
2.8
作者：
Kern, Melanie;Mager, Anke M.;Simon, Jorg
通讯作者：
Simon, Jorg