G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, 5 Science Avenue, Pushchino, Moscow region, 142290, Russia.
J Basic Microbiol. 2011 Jun;51(3):296-303. doi: 10.1002/jobm.201000280. Epub 2011 Feb 7.
Aerobic methylotrophic bacteria able to grow with dichloromethane (DCM) as the sole carbon and energy source possess a specific glutathione S-transferase, DCM dehalogenase, which transforms DCM to formaldehyde, used for biomass and energy production, and hydrochloric acid, which is excreted. Evidence is presented for chloride-specific responses for three DCM-degrading bacteria, Methylobacterium extorquens DM4, Methylopila helvetica DM6 and Albibacter methylovorans DM10. Chloride release into the medium was inhibited by sodium azide and m -chlorophenylhydrazone, suggesting an energy-dependent process. In contrast, only nigericin affected chloride excretion in Mb. extorquens DM4 and Mp. helvetica DM6, while valinomycin had the same effect in A. methylovorans DM10 only. Chloride ions stimulated DCM-dependent induction of DCM dehalogenase expression for Mp. helvetica DM6 and A. methylovorans DM10, and shortened the time for onset of chloride release into the medium. Striking chloride-containing structures were observed by electron microscopy and X-ray microanalysis on the cell surface of Mp. helvetica DM6 and A. methylovorans DM10 during growth with DCM, and with methanol in medium supplemented with sodium chloride. Taken together, these data suggest the existence of both general and specific chloride-associated adaptations in aerobic DCM-degrading bacteria.
能够以二氯甲烷（DCM）作为唯一碳源和能源生长的需氧甲基营养细菌拥有一种特殊的谷胱甘肽 S-转移酶，DCM 脱卤酶，它将 DCM 转化为用于生物量和能量生产的甲醛和盐酸，盐酸被排出体外。本文为三种 DCM 降解细菌，甲基杆菌 DM4、甲基球菌 DM6 和甲基杆菌 DM10 的氯离子特异性反应提供了证据。向培养基中释放氯离子被叠氮化钠和 m-氯苯肼抑制，这表明这是一个依赖能量的过程。相比之下，只有 Nigericin 影响 Mb. extorquens DM4 和 Mp. helvetica DM6 中的氯离子排泄，而 valinomycin 仅在 A. methylovorans DM10 中对氯离子排泄有相同的影响。氯离子刺激 Mp. helvetica DM6 和 A. methylovorans DM10 中 DCM 依赖性诱导 DCM 脱卤酶表达，并缩短了氯离子向培养基中释放的时间。在 DCM 生长过程中以及在含有氯化钠的培养基中添加甲醇时，通过电子显微镜和 X 射线微分析在 Mp. helvetica DM6 和 A. methylovorans DM10 的细胞表面观察到引人注目的含氯结构。综上所述，这些数据表明需氧 DCM 降解细菌中存在一般和特定的与氯离子相关的适应。
