{"title":"Interplay between Amino Acid Substitution in GyrA and QnrB19: Elevating Fluoroquinolone Resistance in <i>Salmonella</i> Typhimurium.","authors":"Pondpan Suwanthada, Siriporn Kongsoi, Sasini Jayaweera, Mwangala Lonah Akapelwa, Jeewan Thapa, Chie Nakajima, Yasuhiko Suzuki","doi":"10.1021/acsinfecdis.4c00150","DOIUrl":null,"url":null,"abstract":"<p><p>Globally, there have been increasing reports of antimicrobial resistance in nontyphoidal <i>Salmonella</i> (NTS), which can develop into severe and potentially life-threatening diarrhea. This study focuses on the synergistic effects of DNA gyrase mutations and plasmid-mediated quinolone resistance (PMQR) genes, specifically <i>qnrB19</i>, on fluoroquinolone (FQ) resistance in <i>Salmonella</i> Typhimurium. By utilizing recombinant mutants, GyrA<sup>S83F</sup> and GyrA<sup>D87N</sup>, and QnrB19's, we discovered a significant increase in fluoroquinolones resistance when QnrB19 is present. Specifically, ciprofloxacin and moxifloxacin's inhibitory concentrations rose 10- and 8-fold, respectively. QnrB19 was found to enhance the resistance capacity of mutant DNA gyrases, leading to high-level FQ resistance. Additionally, we observed that the ratio of QnrB19 to DNA gyrase played a critical role in determining whether QnrB19 could protect DNA gyrase against FQ inhibition. Our findings underscore the critical need to understand these resistance mechanisms, as their coexistence enables bacteria to withstand therapeutic FQ levels, posing a significant challenge to treatment efficacy.</p>","PeriodicalId":17,"journal":{"name":"ACS Infectious Diseases","volume":null,"pages":null},"PeriodicalIF":4.0000,"publicationDate":"2024-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACS Infectious Diseases","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1021/acsinfecdis.4c00150","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, MEDICINAL","Score":null,"Total":0}
引用次数: 0
Abstract
Globally, there have been increasing reports of antimicrobial resistance in nontyphoidal Salmonella (NTS), which can develop into severe and potentially life-threatening diarrhea. This study focuses on the synergistic effects of DNA gyrase mutations and plasmid-mediated quinolone resistance (PMQR) genes, specifically qnrB19, on fluoroquinolone (FQ) resistance in Salmonella Typhimurium. By utilizing recombinant mutants, GyrAS83F and GyrAD87N, and QnrB19's, we discovered a significant increase in fluoroquinolones resistance when QnrB19 is present. Specifically, ciprofloxacin and moxifloxacin's inhibitory concentrations rose 10- and 8-fold, respectively. QnrB19 was found to enhance the resistance capacity of mutant DNA gyrases, leading to high-level FQ resistance. Additionally, we observed that the ratio of QnrB19 to DNA gyrase played a critical role in determining whether QnrB19 could protect DNA gyrase against FQ inhibition. Our findings underscore the critical need to understand these resistance mechanisms, as their coexistence enables bacteria to withstand therapeutic FQ levels, posing a significant challenge to treatment efficacy.
期刊介绍:
ACS Infectious Diseases will be the first journal to highlight chemistry and its role in this multidisciplinary and collaborative research area. The journal will cover a diverse array of topics including, but not limited to:
* Discovery and development of new antimicrobial agents — identified through target- or phenotypic-based approaches as well as compounds that induce synergy with antimicrobials.
* Characterization and validation of drug target or pathways — use of single target and genome-wide knockdown and knockouts, biochemical studies, structural biology, new technologies to facilitate characterization and prioritization of potential drug targets.
* Mechanism of drug resistance — fundamental research that advances our understanding of resistance; strategies to prevent resistance.
* Mechanisms of action — use of genetic, metabolomic, and activity- and affinity-based protein profiling to elucidate the mechanism of action of clinical and experimental antimicrobial agents.
* Host-pathogen interactions — tools for studying host-pathogen interactions, cellular biochemistry of hosts and pathogens, and molecular interactions of pathogens with host microbiota.
* Small molecule vaccine adjuvants for infectious disease.
* Viral and bacterial biochemistry and molecular biology.