Fu Xiuping, Zhang Jingyun, Li Tianyi, Zhang Mei, Li Jie, Kan Biao
State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, China.
Front Microbiol. 2018 Jan 22;8:2703. doi: 10.3389/fmicb.2017.02703. eCollection 2017.
Pathogenic marine bacteria are found in environments and food sources with high salt concentrations, which the bacteria must effectively manage for their survival. Several mechanisms, such as the transport of ions and compatible solutes as well as changes in aerobic and anaerobic respiration, confer salt tolerance to bacteria. In this study, we found that the outer membrane protein OmpW was related to salt stress in and that gene transcription and expression were up-regulated in cultures containing high NaCl concentrations. Deletion of resulted in reduced growth in hypersaline culture conditions. Supplements of the compatible solutes betaine, -carnitine, or -lysine enhanced the growth of in hypersaline media. Supplements of betaine or -lysine had the same growth enhancement effect on the -deletion mutant cultured in hypersaline media, whereas -carnitine supplementation did not restore mutant growth. In addition, the uptake of -carnitine was decreased in the -deletion mutant. Our study showed that among the multiplex factors that enhance the hypersaline tolerance of , OmpW also plays a role by transporting -carnitine.
致病性海洋细菌存在于高盐浓度的环境和食物来源中，细菌必须有效地应对这些环境以生存。几种机制，如离子和相容性溶质的运输以及需氧和厌氧呼吸的变化，赋予了细菌耐盐性。在本研究中，我们发现外膜蛋白OmpW与[细菌名称]的盐胁迫有关，并且在含有高浓度NaCl的培养物中，[细菌名称]基因的转录和表达上调。缺失[细菌名称]基因导致在高盐培养条件下生长减少。添加相容性溶质甜菜碱、γ-肉碱或ε-赖氨酸可增强[细菌名称]在高盐培养基中的生长。甜菜碱或ε-赖氨酸的添加对在高盐培养基中培养的[细菌名称]基因缺失突变体具有相同的生长促进作用，而添加γ-肉碱不能恢复突变体的生长。此外，在[细菌名称]基因缺失突变体中，γ-肉碱的摄取减少。我们的研究表明，在增强[细菌名称]耐高盐性的多种因素中，OmpW还通过转运γ-肉碱发挥作用。
