Chen Xinyi, Tian Jingjing, Luo Can, Wang Xiaofan, Li Xianping, Wang Min
Department of Laboratory Medicine, The Second Xiangya Hospital of Central South University, Changsha, China.
Front Microbiol. 2022 Feb 10;13:810403. doi: 10.3389/fmicb.2022.810403. eCollection 2022.
Polymyxin B (PB) is introduced into the clinic as the last-line therapy against carbapenem-resistant (CRKP). Unfortunately, increased resistance to PB in () has threatened global health. Resistance of to PB was induced by passaging in serial concentrations of PB and determined by microbroth dilution method. Growth characteristics of induced strains including growth curve, reversibility of resistance, and biofilm formation (crystal violet staining method) were measured. This study employed TMT-labeled quantitative proteomics and LC-MS/MS metabolomics analysis to investigate the key biological processes associated with PB resistance in . A total of 315 differentially expressed proteins (DEPs) were identified, of which 133 were upregulated and 182 were downregulated in the PB-resistant . KEGG enrichment analysis revealed that the DEPs were mainly involved in ATP-binding cassette (ABC) transporters and cationic antimicrobial peptide (CAMP) resistance. Proteins related to central carbon metabolism were inhibited in the PB-resistant , but proteins mediating LPS modification were activated. Transcriptional levels of CAMP resistance-related proteins were significantly different between PB-susceptible and -resistant . PB treatment led to an increase in reactive oxygen species (ROS) levels of . Metabolomics data demonstrated that 23 metabolites were significantly upregulated in PB-resistant and 5 were downregulated. The differential metabolites were mainly lipids, including glycerophospholipids, sphingolipids, and fatty acids. Exposure to PB resulted in increased level of phospholipid transport gene in . Our study suggested that membrane remodeling and inhibited central carbon metabolism are conducive to the development of PB resistance in .
多粘菌素B（PB）作为治疗耐碳青霉烯类肺炎克雷伯菌（CRKP）的最后一线疗法被引入临床。不幸的是，肺炎克雷伯菌对PB耐药性的增加威胁着全球健康。通过在连续浓度的PB中传代诱导肺炎克雷伯菌对PB的耐药性，并采用微量肉汤稀释法进行测定。测定了诱导菌株的生长特性，包括生长曲线、耐药性的可逆性和生物膜形成（结晶紫染色法）。本研究采用TMT标记的定量蛋白质组学和LC-MS/MS代谢组学分析，以研究肺炎克雷伯菌中与PB耐药相关的关键生物学过程。共鉴定出315个差异表达蛋白（DEP），其中133个在耐PB的肺炎克雷伯菌中上调，182个下调。KEGG富集分析表明，DEP主要参与ATP结合盒（ABC）转运蛋白和阳离子抗菌肽（CAMP）耐药。与中心碳代谢相关的蛋白在耐PB的肺炎克雷伯菌中受到抑制，但介导脂多糖修饰的蛋白被激活。CAMP耐药相关蛋白的转录水平在PB敏感和耐药的肺炎克雷伯菌之间存在显著差异。PB处理导致肺炎克雷伯菌活性氧（ROS）水平升高。代谢组学数据表明，23种代谢物在耐PB的肺炎克雷伯菌中显著上调，5种下调。差异代谢物主要是脂质，包括甘油磷脂、鞘脂和脂肪酸。暴露于PB导致肺炎克雷伯菌中磷脂转运基因水平升高。我们的研究表明，膜重塑和中心碳代谢受抑制有利于肺炎克雷伯菌中PB耐药性的发展。
