School of Life Sciences, Central China Normal University, Wuhan, China
mSphere. 2018 Apr 11;3(2). doi: 10.1128/mSphere.00095-18. Print 2018 Apr 25.
Environmental stresses often co-occur when bacteria encounter antibiotic treatment inside the human body. The cellular response to environmental stressors can alter the global gene expression pattern of bacteria. However, the relationship between the cellular stress response and antibiotic susceptibility remains poorly understood. Here we studied the effect of high salt, an important environmental stress condition inside the human body, on bacterial susceptibility to antibiotics. We found that high salt reduces the susceptibility of to tetracycline and chloramphenicol, leading to a cross-protection effect. The cross-protection effect originates from the increased AcrAB-TolC efflux pump expression level under high-salt conditions. Our study demonstrates that stress-induced gene expression alterations can cross-protect bacteria from antibiotic treatment and should thus be considered when investigating antibiotic susceptibility and applying antimicrobial treatment. Environmental stresses often co-occur when bacteria confront antibiotic treatment. We provide a clear example that a natural stress condition (high salt) can cross-protect bacteria from antibiotic treatment by triggering the bacterial stress response program (elevated AcrAB-TolC efflux pump expression). Our study highlights the importance of taking the co-occurrence of bacterial environmental stresses into consideration when investigating antibiotic susceptibility and applying antimicrobial treatment.
当细菌在人体内遇到抗生素治疗时，环境压力通常会同时出现。细菌对环境胁迫的细胞反应会改变细菌的全局基因表达模式。然而，细胞应激反应与抗生素敏感性之间的关系仍知之甚少。在这里，我们研究了高盐（人体内的一种重要环境应激条件）对细菌对抗生素敏感性的影响。我们发现，高盐会降低对四环素和氯霉素的敏感性，从而产生交叉保护作用。这种交叉保护作用源于高盐条件下 AcrAB-TolC 外排泵表达水平的增加。我们的研究表明，应激诱导的基因表达改变可以使细菌免受抗生素治疗的影响，因此在研究抗生素敏感性和应用抗菌治疗时应考虑这一点。当细菌面临抗生素治疗时，环境压力通常会同时出现。我们提供了一个明确的例子，即自然应激条件（高盐）可以通过触发细菌应激反应程序（AcrAB-TolC 外排泵表达升高）来保护细菌免受抗生素治疗。我们的研究强调了在研究抗生素敏感性和应用抗菌治疗时，考虑细菌环境压力的共同发生的重要性。
