{"title":"Dynamic responses of Salmonella Typhimurium to re-exposure to sublethal ciprofloxacin","authors":"Jiseok Yi, Junhwan Kim, Juhee Ahn","doi":"10.1093/femsle/fnae050","DOIUrl":null,"url":null,"abstract":"This study was designed to evaluate the history-dependent behaviors of Salmonella Typhimurium re-exposed to sublethal levels of ciprofloxacin. The S. Typhimurium cells were pre-exposed to 0 (CON), 1/16 (LOW), 1/8 (MED), and 1/4 (HIGH) MICs of ciprofloxacin, followed by re-exposure to the same concentrations. The bacterial growth, post-antibiotic effect (PAE), relative fitness, and swimming motility of treatments were evaluated in the absence of ciprofloxacin. The lag phase duration (LPD) was estimate to assess bacterial recovery under ciprofloxacin exposure. A disk diffusion assay was used to determine the cross-resistance and collateral sensitivity of CON, LOW, MED, and HIGH treatments to ciprofloxacin (CIP), ceftriaxone (CEF), erythromycin (ERY), gentamicin (GEN), and polymyxin B (POL). The S. Typhimurium cells pre-exposed to ciprofloxacin were susceptible in antibiotic-free media, showing delayed growth. The highest PAE (> 1 h) and bacterial fluctuation (CV = 5%) were observed at the High treatment compared to the CON. The HIGH treatment had the lowest relative fitness levels (0.87) and swimming motility (55 mm). The LPD was significantly decreased at the LOW treatment (1.8 h) when re-exposed to 1/16× MIC of ciprofloxacin. The LOW, MED, and HIGH treatments showed the cross-resistance to POL and the collateral sensitivity to CEF, ERY, and GEN. The pre-exposure to ciprofloxacin could induce phenotypic diversity, corresponding to the history-dependent behaviors. These results provide important insights for the dynamic nature of bacterial populations when re-exposed to sublethal concentrations of antibiotics.","PeriodicalId":12214,"journal":{"name":"Fems Microbiology Letters","volume":"140 1","pages":""},"PeriodicalIF":2.2000,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Fems Microbiology Letters","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1093/femsle/fnae050","RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MICROBIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
This study was designed to evaluate the history-dependent behaviors of Salmonella Typhimurium re-exposed to sublethal levels of ciprofloxacin. The S. Typhimurium cells were pre-exposed to 0 (CON), 1/16 (LOW), 1/8 (MED), and 1/4 (HIGH) MICs of ciprofloxacin, followed by re-exposure to the same concentrations. The bacterial growth, post-antibiotic effect (PAE), relative fitness, and swimming motility of treatments were evaluated in the absence of ciprofloxacin. The lag phase duration (LPD) was estimate to assess bacterial recovery under ciprofloxacin exposure. A disk diffusion assay was used to determine the cross-resistance and collateral sensitivity of CON, LOW, MED, and HIGH treatments to ciprofloxacin (CIP), ceftriaxone (CEF), erythromycin (ERY), gentamicin (GEN), and polymyxin B (POL). The S. Typhimurium cells pre-exposed to ciprofloxacin were susceptible in antibiotic-free media, showing delayed growth. The highest PAE (> 1 h) and bacterial fluctuation (CV = 5%) were observed at the High treatment compared to the CON. The HIGH treatment had the lowest relative fitness levels (0.87) and swimming motility (55 mm). The LPD was significantly decreased at the LOW treatment (1.8 h) when re-exposed to 1/16× MIC of ciprofloxacin. The LOW, MED, and HIGH treatments showed the cross-resistance to POL and the collateral sensitivity to CEF, ERY, and GEN. The pre-exposure to ciprofloxacin could induce phenotypic diversity, corresponding to the history-dependent behaviors. These results provide important insights for the dynamic nature of bacterial populations when re-exposed to sublethal concentrations of antibiotics.
期刊介绍:
FEMS Microbiology Letters gives priority to concise papers that merit rapid publication by virtue of their originality, general interest and contribution to new developments in microbiology. All aspects of microbiology, including virology, are covered.
2019 Impact Factor: 1.987, Journal Citation Reports (Source Clarivate, 2020)
Ranking: 98/135 (Microbiology)
The journal is divided into eight Sections:
Physiology and Biochemistry (including genetics, molecular biology and ‘omic’ studies)
Food Microbiology (from food production and biotechnology to spoilage and food borne pathogens)
Biotechnology and Synthetic Biology
Pathogens and Pathogenicity (including medical, veterinary, plant and insect pathogens – particularly those relating to food security – with the exception of viruses)
Environmental Microbiology (including ecophysiology, ecogenomics and meta-omic studies)
Virology (viruses infecting any organism, including Bacteria and Archaea)
Taxonomy and Systematics (for publication of novel taxa, taxonomic reclassifications and reviews of a taxonomic nature)
Professional Development (including education, training, CPD, research assessment frameworks, research and publication metrics, best-practice, careers and history of microbiology)
If you are unsure which Section is most appropriate for your manuscript, for example in the case of transdisciplinary studies, we recommend that you contact the Editor-In-Chief by email prior to submission. Our scope includes any type of microorganism - all members of the Bacteria and the Archaea and microbial members of the Eukarya (yeasts, filamentous fungi, microbial algae, protozoa, oomycetes, myxomycetes, etc.) as well as all viruses.