Contribution of Different Mechanisms to Ciprofloxacin Resistance in Salmonella spp.
Contribution of Different Mechanisms to Ciprofloxacin Resistance in Salmonella spp.
复制标题
不同机制对沙门氏菌对环丙沙星耐药的贡献。
DOI：
10.3389/fmicb.2021.663731
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发表时间：
2021
影响因子：
5.2
通讯作者：
Jiang HX
中科院分区：
文献类型：
--
作者：
Chang MX;Zhang JF;Sun YH;Li RS;Lin XL;Yang L;Webber MA;Jiang HX
氟喹诺酮类药物耐药的发生可能涉及多种机制，包括编码目标细菌拓扑异构酶的基因（gyrAB和parCE）的染色体突变，AcrAB-TolC外排系统的表达增加，以及获得可传播的喹诺酮类药物耐药基因。本研究收集了176株具有广泛环丙沙星mic的动物沙门氏菌，分析了这些不同机制对不同表型的贡献。所有分离株根据对环丙沙星的药敏类型分为高耐药（HR）、耐药(R)、中耐药(I)、降低药敏（RS）和敏感(S) 5组。我们发现ParC T57S替代在环丙沙星mic最低的菌株中很常见，而mic的增加取决于GyrA突变的类型。ParC T57S替代似乎对细菌自身的适应度几乎没有影响。PMQR基因的存在代表了在没有靶位点突变的情况下耐药发展的途径。观察到质粒介导的喹诺酮耐药（PMQR）基因从质粒转移到染色体，导致环丙沙星敏感性降低；这也与增强的适应性和稳定的抗性表型相关。acrabb - tolc的过表达在敏感性降低的分离株中起重要作用，并且MarA比RamA更频繁地上调表达。这项研究增加了我们对沙门氏菌从食物链中产生氟喹诺酮类药物耐药性的几种耐药机制的相对重要性的理解。
Development of fluoroquinolone resistance can involve several mechanisms that include chromosomal mutations in genes (gyrAB and parCE) encoding the target bacterial topoisomerase enzymes, increased expression of the AcrAB-TolC efflux system, and acquisition of transmissible quinolone-resistance genes. In this study, 176 Salmonella isolates from animals with a broad range of ciprofloxacin MICs were collected to analyze the contribution of these different mechanisms to different phenotypes. All isolates were classified according to their ciprofloxacin susceptibility pattern into five groups as follows: highly resistant (HR), resistant (R), intermediate (I), reduced susceptibility (RS), and susceptible (S). We found that the ParC T57S substitution was common in strains exhibiting lowest MICs of ciprofloxacin while increased MICs depended on the type of GyrA mutation. The ParC T57S substitution appeared to incur little cost to bacterial fitness on its own. The presence of PMQR genes represented an route for resistance development in the absence of target-site mutations. Switching of the plasmid-mediated quinolone resistance (PMQR) gene location from a plasmid to the chromosome was observed and resulted in decreased ciprofloxacin susceptibility; this also correlated with increased fitness and a stable resistance phenotype. The overexpression of AcrAB-TolC played an important role in isolates with small decreases in susceptibility and expression was upregulated by MarA more often than by RamA. This study increases our understanding of the relative importance of several resistance mechanisms in the development of fluoroquinolone resistance in Salmonella from the food chain.
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影响因子：
5.2
作者：
Fabrega, Anna;Balleste-Delpierre, Clara;Vila, Jordi
通讯作者：
Vila, Jordi
影响因子：
2.6
作者：
Norman, Anders;Hansen, Lars Hestbjerg;Sorensen, Soren Johannes
通讯作者：
Sorensen, Soren Johannes
影响因子：
4.9
作者：
Ling, JM;Chan, EW;Cheng, AF
通讯作者：
Cheng, AF
影响因子：
5.2
作者：
Blair, Jessica M. A.;La Ragione, Roberto M.;Piddock, Laura J. V.
通讯作者：
Piddock, Laura J. V.
影响因子：
11.8
作者：
Hohmann, EL
通讯作者：
Hohmann, EL