The fitness cost of antibiotic resistance is a crucial factor to determine the evolutionary and transmission success of resistant bacteria. Exploring the fitness cost and compensation mechanism of antibiotic resistance genes (ARGs) in bacteria may effectively reduce the transmission of drug-resistant genes in the environment. Engineered bacteria with the same genetic background that carry sulfonamide resistance gene were generated to explore the fitness cost of sulfonamide resistance gene in Escherichia coli. There were significant differences in the protein expression of the two-component system pathway (fliZ, fliA, fliC and lrhA), folate biosynthesis pathway (sul1, sul2 and sul3), ABC transporter system (ugpC, rbsA and gsiA), and outer membrane pore protein OmpD through the comparative analysis of differential proteins compared to sensitive bacteria. Thus, we could speculate the possible fitness compensation mechanism. Finally, quantitative Real-time PCR (qRT-PCR) was used to verify the functions of some differential proteins at the transcriptional level. The fitness cost and compensatory evolution of antibiotic resistance are an essential part of bacterial evolution.

中文翻译：

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大肠埃希菌磺胺类耐药基因（sul1、sul2、sul3）的适应度成本及补偿机制

抗生素耐药性的适应度成本是决定耐药菌进化和传播成功的关键因素。探索细菌中抗生素耐药基因（ARGs）的适应度成本和补偿机制，可以有效减少耐药基因在环境中的传播。构建具有相同遗传背景且携带磺胺类抗性基因的工程菌，探讨磺胺类抗性基因在大肠杆菌中的适应性成本。双组分系统途径（fliZ、fliA、fliC和lrhA）、叶酸生物合成途径（sul1、sul2和sul3 )、ABC 转运蛋白系统 ( ugpC、rbsA和gsiA ) 和外膜孔蛋白 OmpD 通过与敏感细菌相比差异蛋白的比较分析。因此，我们可以推测可能的适应度补偿机制。最后，使用定量实时PCR（qRT-PCR）在转录水平验证一些差异蛋白的功能。抗生素耐药性的适应性成本和补偿性进化是细菌进化的重要组成部分。