摘要

近年来，嗜水气单胞菌已被列为食源性病原体，其抗生素抗性水平增加，对这种抗性的机制了解甚少。在这项研究中，iTRAQ偶联质谱法被用来比较金霉素（CTC）抗性嗜水气单胞菌相对于对照菌株中差异表达的蛋白质。结果表明，在金霉素抗性品系中共鉴定出234个差异蛋白，其中151个下调，83个上调。生物信息学分析表明，除了先前报道的三羧酸循环（TCA）相关蛋白质之外，与CheA-2，CheR-3，CheW-2，EnvZ，PolA，FliS和FliG等趋化相关蛋白质也被下调，调控。然后通过蛋白质印迹进一步验证所鉴定的差异表达蛋白质的子集。外源代谢物与四氯化碳联合进一步提高了嗜水气单胞菌对细菌的敏感性。此外，细菌存活能力测定表明，几种趋化性相关突变体，例如ΔcheR-3和ΔAHA_0305可能影响嗜水气单胞菌的抗微生物药物敏感性。总体而言，这些发现有助于进一步了解嗜水气单胞菌中CTC抗性的机制，并可能有助于开发更有效的未来治疗方法。

In recent years, Aeromonas hydrophila, which has been classified as a food borne pathogen, has presented with increased levels of antibiotic resistance, with the mechanisms of this resistance being poorly understood. In this study, iTRAQ coupled mass spectrometry was employed to compare differentially expressed proteins in chlortetracycline (CTC) resistant A.hydrophila relative to a control strain. Result showed that a total of 234 differential proteins including 151 down-regulated and 83 up-regulated were identified in chlortetracycline resistance strain. Bioinformatics analysis showed that chemotaxis related proteins, such as CheA-2, CheR-3, CheW-2, EnvZ, PolA, FliS and FliG were down-regulated in addition to previously reported tricarboxylic acid cycle (TCA) related proteins also being down-regulated. A subset of identified differentially expressed proteins was then further validated via Western blotting. Exogenous metabolite combined with CTC further enhanced the bacterial susceptibilities to CTC in A. hydrophila. Furthermore, a bacterial survival capability assay showed that several chemotaxis related mutants, such as ΔcheR-3 and ΔAHA_0305, may affect the antimicrobial susceptibility of A. hydrophila. Overall, these findings contribute to a further understanding of the mechanism of CTC resistance in A. hydrophila and may contribute to the development of more effective future treatments.

https://www.sciencedirect.com/science/article/pii/S1874391917303251