Aix Marseille Université, Université de Toulon, CNRS, IRD, MIO, Marseille, France.
Aix Marseille Université, CNRS, LCB, Marseille, France.
Environ Microbiol. 2019 Jan;21(1):360-373. doi: 10.1111/1462-2920.14466. Epub 2018 Dec 3.
Desulfovibrio species are representatives of microorganisms at the boundary between anaerobic and aerobic lifestyles, since they contain the enzymatic systems required for both sulfate and oxygen reduction. However, the latter has been shown to be solely a protective mechanism. By implementing the oxygen-driven experimental evolution of Desulfovibrio vulgaris Hildenborough, we have obtained strains that have evolved to grow with energy derived from oxidative phosphorylation linked to oxygen reduction. We show that a few mutations are sufficient for the emergence of this phenotype and reveal two routes of evolution primarily involving either inactivation or overexpression of the gene encoding heterodisulfide reductase. We propose that the oxygen respiration for energy conservation that sustains the growth of the O -evolved strains is associated with a rearrangement of metabolite fluxes, especially NAD /NADH, leading to an optimized O reduction. These evolved strains are the first sulfate-reducing bacteria that exhibit a demonstrated oxygen respiratory process that enables growth.
脱硫弧菌属物种是兼性厌氧和需氧生活方式之间微生物的代表，因为它们包含硫酸盐和氧气还原所需的酶系统。然而，后者已被证明仅仅是一种保护机制。通过对希氏脱硫弧菌进行有氧驱动的实验进化，我们获得了能够从与氧气还原偶联的氧化磷酸化中获取能量生长的菌株。我们表明，少数突变足以产生这种表型，并揭示了两种进化途径，主要涉及杂二硫化物还原酶编码基因的失活或过表达。我们提出，维持 O 进化菌株生长的用于能量保存的氧气呼吸与代谢物通量的重新排列有关，特别是 NAD/NADH，从而导致优化的 O 还原。这些进化而来的菌株是首个表现出证明的氧气呼吸过程的硫酸盐还原菌，使其能够生长。
