{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,7]],"date-time":"2026-05-07T17:44:23Z","timestamp":1778175863552,"version":"3.51.4"},"reference-count":58,"publisher":"Akademiai Kiado Zrt.","issue":"2","content-domain":{"domain":["akjournals.com"],"crossmark-restriction":true},"short-container-title":["AMicr"],"published-print":{"date-parts":[[2018,11,22]]},"abstract":"Fluoroquinolone resistance in Enterobacteriales is developed by chromosomal and plasmid-mediated mechanisms. Plasmids play an important role in dissemination of resistant genes and they carry genes that protect bacteria in different stress-induced situations. In this study, we studied Escherichia coli<\/jats:italic> strains, each carried one plasmid-mediated quinolone resistance determinant namely, qnrA1, qnrB1, qnrC1<\/jats:italic>, and qnrD1.<\/jats:italic> We exposed 0.5 McFarland density of each strain to 0.5\u2009mg\/L ciprofloxacin from the period of 30, 60, 90, and 120\u00a0min over 24\u00a0h. All treated strains were further exposed to a constantly increasing 1, 2, 4, and 8\u2009mg\/L ciprofloxacin solution through 24, 48, and 120\u00a0h. In given timepoints, RNA was extracted from all treated strains. Expression of qnrA1, qnrB1, qnrC1<\/jats:italic>, and qnrD1<\/jats:italic> was investigated by quantitative PCR. Mutations in gyrA<\/jats:italic> and parC<\/jats:italic> genes were analyzed by PCR and nucleic acid sequencing. In this study, during 0.5\u2009mg\/L ciprofloxacin exposition, the following expression levels were detected: 1.2 for qnrA1<\/jats:italic>, 1.47 for qnrD1<\/jats:italic>, 12.44 for qnrC1<\/jats:italic>, and 80.63 for qnrB1<\/jats:italic>. In case of long-term study, we selected a resistant strain in qnrB1<\/jats:italic>-positive E. coli<\/jats:italic>, and its expression increased from 105.91 to 212.31. On the contrary, plasmid copy number increased in time from 1 to 4.13. No mutations in gyrA<\/jats:italic> or in parC<\/jats:italic> chromosomal genes of treated strains were detected. Our results show that qnrB1<\/jats:italic>-positive E. coli<\/jats:italic> strain was able to develop fluoroquinolone resistance by upregulated qnrB1<\/jats:italic> expression that was linked to a minor increase in plasmid copy number but no mutations occurred in gyrA<\/jats:italic> or parC.<\/jats:italic><\/jats:p>","DOI":"10.1556\/030.65.2018.049","type":"journal-article","created":{"date-parts":[[2018,11,22]],"date-time":"2018-11-22T11:04:55Z","timestamp":1542884695000},"page":"169-178","update-policy":"https:\/\/doi.org\/10.1556\/policypage.crossmark.crossref.1","source":"Crossref","is-referenced-by-count":5,"title":["Plasmid copy number and qnr gene expression in selection of fluoroquinolone-resistant Escherichia coli"],"prefix":"10.1556","volume":"66","author":[{"given":"D\u00e1niel","family":"Guly\u00e1s","sequence":"first","affiliation":[{"name":"1 Institute of Medical Microbiology, Semmelweis University, Budapest, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"B\u00e9la","family":"Kocsis","sequence":"additional","affiliation":[{"name":"1 Institute of Medical Microbiology, Semmelweis University, Budapest, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"D\u00f3ra","family":"Szab\u00f3","sequence":"additional","affiliation":[{"name":"1 Institute of Medical Microbiology, Semmelweis University, Budapest, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"425","reference":[{"key":"ref301","doi-asserted-by":"crossref","first-page":"438","DOI":"10.1016\/j.tim.2014.04.007","article-title":"Fluoroquinolone resistance: Mechanisms, impact on bacteria, and role in evolutionary success","volume":"22","author":"Redgrave","year":"2014","journal-title":"Trends Microbiol"},{"key":"ref211","doi-asserted-by":"crossref","first-page":"1007","DOI":"10.2147\/IDR.S160720","article-title":"The prevalence of plasmid-mediated quinolone resistance and ESBL-production in Enterobacteriaceae isolated from urinary tract infections","volume":"11","author":"Azargun","year":"2018","journal-title":"Infect Drug Resist"},{"key":"ref371","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1016\/j.drup.2016.09.001","article-title":"Plasmid-mediated quinolone resistance: Two decades on","volume":"29","author":"Rodr\u00edguez-Mart\u00ednez","year":"2016","journal-title":"Drug Resist Updat"},{"key":"ref501","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1038\/nm1347","article-title":"Fluoroquinolone-modifying enzyme: A new adaptation of a common aminoglycoside acetyltransferase","volume":"12","author":"Robicsek","year":"2006","journal-title":"Nat Med"},{"key":"ref531","doi-asserted-by":"crossref","first-page":"313","DOI":"10.1556\/030.63.2016.002","article-title":"Plasmid-mediated quinolone resistance among extended-spectrum beta-lactamase producing Enterobacteriaceae from bloodstream infections","volume":"63","author":"Domokos","year":"2016","journal-title":"Acta Microbiol Immunol Hung"},{"key":"ref461","doi-asserted-by":"crossref","first-page":"2680","DOI":"10.1128\/AAC.00158-08","article-title":"Presence of plasmid-mediated quinolone resistance in Klebsiella pneumoniae isolates possessing blaKPC in the United States","volume":"52","author":"Endimiani","year":"2008","journal-title":"Antimicrob Agents Chemother"},{"key":"ref511","doi-asserted-by":"crossref","first-page":"1007","DOI":"10.2147\/IDR.S160720","article-title":"The prevalence of plasmid-mediated quinolone resistance and ESBL-production in Enterobacteriaceae isolated from urinary tract infections","volume":"11","author":"Azargun","year":"2018","journal-title":"Infect Drug Resist"},{"key":"ref541","article-title":"http www lahey org qnrStudies"},{"key":"ref01","doi-asserted-by":"crossref","first-page":"438","DOI":"10.1016\/j.tim.2014.04.007","article-title":"Fluoroquinolone resistance: Mechanisms, impact on bacteria, and role in evolutionary success","volume":"22","author":"Redgrave","year":"2014","journal-title":"Trends Microbiol"},{"key":"ref271","doi-asserted-by":"crossref","first-page":"338","DOI":"10.7150\/ijbs.4.338","article-title":"Inducible SOS response system of DNA repair and mutagenesis in Escherichia coli","volume":"4","author":"Janion","year":"2008","journal-title":"Int J Biol Sci"},{"key":"ref41","doi-asserted-by":"crossref","first-page":"570","DOI":"10.1038\/nrurol.2015.199","article-title":"The emerging threat of multidrug-resistant Gram-negative bacteria in urology","volume":"12","author":"Zowawi","year":"2015","journal-title":"Nat Rev Urol"},{"key":"ref561","doi-asserted-by":"crossref","first-page":"929","DOI":"10.1038\/embor.2009.99","article-title":"The SOS-response promotes qnrB quinolone-resistance determinant expression","volume":"10","author":"Da Re","year":"2009","journal-title":"EMBO Rep"},{"key":"ref131","doi-asserted-by":"crossref","first-page":"421","DOI":"10.1007\/s10096-016-2847-x","article-title":"Plasmid-mediated quinolone resistance in Enterobacteriaceae: A systematic review with a focus on Mediterranean countries","volume":"36","author":"Yanat","year":"2017","journal-title":"Eur J Clin Microbiol Infect Dis"},{"key":"ref181","doi-asserted-by":"crossref","first-page":"2581","DOI":"10.1128\/AAC.01540-07","article-title":"Sequence of conjugative plasmid pIP1206 mediating resistance to aminoglycosides by 16s rRNA methylation and to hydrophilic fluoroquinolones by efflux","volume":"52","author":"Perichon","year":"2008","journal-title":"Antimicrob Agents Chemother"},{"key":"ref201","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1038\/nm1347","article-title":"Fluoroquinolone-modifying enzyme: A new adaptation of a common aminoglycoside acetyltransferase","volume":"12","author":"Robicsek","year":"2006","journal-title":"Nat Med"},{"key":"ref251","doi-asserted-by":"crossref","first-page":"821","DOI":"10.1128\/AAC.00132-08","article-title":"SOS regulation of qnrB expression","volume":"53","author":"Wang","year":"2009","journal-title":"Antimicrob Agents Chemother"},{"key":"ref311","first-page":"24","volume-title":"Guidelines on Urological Infections","author":"Grabe","year":"2015"},{"key":"ref441","doi-asserted-by":"crossref","first-page":"149","DOI":"10.1007\/s10156-010-0120-2","article-title":"Plasmid-mediated quinolone resistance: An update","volume":"17","author":"Rodr\u00edguez-Mart\u00ednez","year":"2011","journal-title":"J Infect Chemother"},{"key":"ref451","doi-asserted-by":"crossref","first-page":"1725","DOI":"10.1093\/jac\/dkr222","article-title":"Extended-spectrum \u03b2-lactamases and plasmid-mediated quinolone resistance in enterobacterial clinical isolates in the paediatric hospital of Uruguay","volume":"66","author":"Garc\u00eda-Fulgueiras","year":"2011","journal-title":"J Antimicrob Chemother"},{"key":"ref221","doi-asserted-by":"crossref","first-page":"255","DOI":"10.1556\/030.65.2018.012","article-title":"Plasmid-mediated quinolone resistance determinants in Enterobacteriaceae from urine clinical samples","volume":"65","author":"Szab\u00f3","year":"2018","journal-title":"Acta Microbiol Immunol Hung"},{"key":"ref291","first-page":"91","volume-title":"The Sanford Guide to Antimicrobial Therapy","author":"Sanford","year":"2017"},{"key":"ref581","article-title":"http www eucast org clinical breakpoints"},{"key":"ref331","doi-asserted-by":"crossref","first-page":"268","DOI":"10.3390\/molecules21040268","article-title":"The current case of quinolones: Synthetic approaches and antibacterial activity","volume":"21","author":"Naeem","year":"2016","journal-title":"Molecules"},{"key":"ref421","doi-asserted-by":"crossref","first-page":"750","DOI":"10.1128\/MMBR.00015-09","article-title":"Pathogenomics of the virulence plasmids of Escherichia coli","volume":"73","author":"Johnson","year":"2009","journal-title":"Microbiol Mol Biol Rev"},{"key":"ref571","doi-asserted-by":"crossref","first-page":"338","DOI":"10.7150\/ijbs.4.338","article-title":"Inducible SOS response system of DNA repair and mutagenesis in Escherichia coli","volume":"4","author":"Janion","year":"2008","journal-title":"Int J Biol Sci"},{"key":"ref31","doi-asserted-by":"crossref","first-page":"268","DOI":"10.3390\/molecules21040268","article-title":"The current case of quinolones: Synthetic approaches and antibacterial activity","volume":"21","author":"Naeem","year":"2016","journal-title":"Molecules"},{"key":"ref111","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1264\/jsme2.ME10155","article-title":"The behavior and significance of degradative plasmids belonging to Inc groups in Pseudomonas within natural environments and microcosms","volume":"25","author":"Shintani","year":"2010","journal-title":"Microbes Environ"},{"key":"ref241","article-title":"http www lahey org qnrStudies"},{"key":"ref121","doi-asserted-by":"crossref","first-page":"750","DOI":"10.1128\/MMBR.00015-09","article-title":"Pathogenomics of the virulence plasmids of Escherichia coli","volume":"73","author":"Johnson","year":"2009","journal-title":"Microbiol Mol Biol Rev"},{"key":"ref381","doi-asserted-by":"crossref","first-page":"2227","DOI":"10.1128\/AAC.01707-08","article-title":"Resistance plasmid families in Enterobacteriaceae","volume":"53","author":"Carattoli","year":"2009","journal-title":"Antimicrob Agents Chemother"},{"key":"ref11","first-page":"24","volume-title":"Guidelines on Urological Infections","author":"Grabe","year":"2015"},{"key":"ref491","doi-asserted-by":"crossref","first-page":"664","DOI":"10.1128\/CMR.00016-09","article-title":"Plasmid-mediated quinolone resistance: A multifaceted threat","volume":"22","author":"Strahilevitz","year":"2009","journal-title":"Clin Microbiol Rev"},{"key":"ref91","doi-asserted-by":"crossref","first-page":"711","DOI":"10.1038\/nrmicro1234","article-title":"Mechanisms of, and barriers to, horizontal gene transfer between bacteria","volume":"3","author":"Thomas","year":"2005","journal-title":"Nat Rev Microbiol"},{"key":"ref141","doi-asserted-by":"crossref","first-page":"149","DOI":"10.1007\/s10156-010-0120-2","article-title":"Plasmid-mediated quinolone resistance: An update","volume":"17","author":"Rodr\u00edguez-Mart\u00ednez","year":"2011","journal-title":"J Infect Chemother"},{"key":"ref151","doi-asserted-by":"crossref","first-page":"1725","DOI":"10.1093\/jac\/dkr222","article-title":"Extended-spectrum \u03b2-lactamases and plasmid-mediated quinolone resistance in enterobacterial clinical isolates in the paediatric hospital of Uruguay","volume":"66","author":"Garc\u00eda-Fulgueiras","year":"2011","journal-title":"J Antimicrob Chemother"},{"key":"ref591","first-page":"91","volume-title":"The Sanford Guide to Antimicrobial Therapy","author":"Sanford","year":"2017"},{"key":"ref191","doi-asserted-by":"crossref","first-page":"664","DOI":"10.1128\/CMR.00016-09","article-title":"Plasmid-mediated quinolone resistance: A multifaceted threat","volume":"22","author":"Strahilevitz","year":"2009","journal-title":"Clin Microbiol Rev"},{"key":"ref261","doi-asserted-by":"crossref","first-page":"929","DOI":"10.1038\/embor.2009.99","article-title":"The SOS-response promotes qnrB quinolone-resistance determinant expression","volume":"10","author":"Da Re","year":"2009","journal-title":"EMBO Rep"},{"key":"ref171","doi-asserted-by":"crossref","first-page":"186","DOI":"10.1089\/mdr.2014.0073","article-title":"Characterization of extended-spectrum beta-lactamase, carbapenemase and plasmid quinolone determinants in Klebsiella pneumoniae isolates carrying distinct types of 16s rRNA methylase genes and their association with mobile genetic elements","volume":"21","author":"Wei","year":"2015","journal-title":"Microb Drug Resist"},{"key":"ref321","first-page":"462","article-title":"A more restrictive use of quinolones in patients with community acquired pneumonia is urgently needed","volume":"75","author":"Van Berge Henegouwen","year":"2017","journal-title":"Neth J Med"},{"key":"ref61","doi-asserted-by":"crossref","first-page":"797","DOI":"10.1016\/S0140-6736(97)07322-4","article-title":"Quinolone resistance from a transferable plasmid","volume":"351","author":"Mart\u00ednez-Mart\u00ednez","year":"1998","journal-title":"Lancet"},{"key":"ref81","doi-asserted-by":"crossref","first-page":"2227","DOI":"10.1128\/AAC.01707-08","article-title":"Resistance plasmid families in Enterobacteriaceae","volume":"53","author":"Carattoli","year":"2009","journal-title":"Antimicrob Agents Chemother"},{"key":"ref101","doi-asserted-by":"crossref","first-page":"569","DOI":"10.1128\/jb.147.2.569-577.1981","article-title":"Identification and characterization of Col plasmids from classical colicin E-producing strains","volume":"147","author":"Watson","year":"1981","journal-title":"J Bacteriol"},{"key":"ref281","article-title":"http www eucast org clinical breakpoints"},{"key":"ref431","doi-asserted-by":"crossref","first-page":"421","DOI":"10.1007\/s10096-016-2847-x","article-title":"Plasmid-mediated quinolone resistance in Enterobacteriaceae: A systematic review with a focus on Mediterranean countries","volume":"36","author":"Yanat","year":"2017","journal-title":"Eur J Clin Microbiol Infect Dis"},{"key":"ref161","doi-asserted-by":"crossref","first-page":"2680","DOI":"10.1128\/AAC.00158-08","article-title":"Presence of plasmid-mediated quinolone resistance in Klebsiella pneumoniae isolates possessing blaKPC in the United States","volume":"52","author":"Endimiani","year":"2008","journal-title":"Antimicrob Agents Chemother"},{"key":"ref231","doi-asserted-by":"crossref","first-page":"313","DOI":"10.1556\/030.63.2016.002","article-title":"Plasmid-mediated quinolone resistance among extended-spectrum beta-lactamase producing Enterobacteriaceae from bloodstream infections","volume":"63","author":"Domokos","year":"2016","journal-title":"Acta Microbiol Immunol Hung"},{"key":"ref401","doi-asserted-by":"crossref","first-page":"569","DOI":"10.1128\/jb.147.2.569-577.1981","article-title":"Identification and characterization of Col plasmids from classical colicin E-producing strains","volume":"147","author":"Watson","year":"1981","journal-title":"J Bacteriol"},{"key":"ref341","doi-asserted-by":"crossref","first-page":"570","DOI":"10.1038\/nrurol.2015.199","article-title":"The emerging threat of multidrug-resistant Gram-negative bacteria in urology","volume":"12","author":"Zowawi","year":"2015","journal-title":"Nat Rev Urol"},{"key":"ref551","doi-asserted-by":"crossref","first-page":"821","DOI":"10.1128\/AAC.00132-08","article-title":"SOS regulation of qnrB expression","volume":"53","author":"Wang","year":"2009","journal-title":"Antimicrob Agents Chemother"},{"key":"ref21","first-page":"462","article-title":"A more restrictive use of quinolones in patients with community acquired pneumonia is urgently needed","volume":"75","author":"Van Berge Henegouwen","year":"2017","journal-title":"Neth J Med"},{"key":"ref481","doi-asserted-by":"crossref","first-page":"2581","DOI":"10.1128\/AAC.01540-07","article-title":"Sequence of conjugative plasmid pIP1206 mediating resistance to aminoglycosides by 16s rRNA methylation and to hydrophilic fluoroquinolones by efflux","volume":"52","author":"Perichon","year":"2008","journal-title":"Antimicrob Agents Chemother"},{"key":"ref521","doi-asserted-by":"crossref","first-page":"255","DOI":"10.1556\/030.65.2018.012","article-title":"Plasmid-mediated quinolone resistance determinants in Enterobacteriaceae from urine clinical samples","volume":"65","author":"Szab\u00f3","year":"2018","journal-title":"Acta Microbiol Immunol Hung"},{"key":"ref71","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1016\/j.drup.2016.09.001","article-title":"Plasmid-mediated quinolone resistance: Two decades on","volume":"29","author":"Rodr\u00edguez-Mart\u00ednez","year":"2016","journal-title":"Drug Resist Updat"},{"key":"ref411","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1264\/jsme2.ME10155","article-title":"The behavior and significance of degradative plasmids belonging to Inc groups in Pseudomonas within natural environments and microcosms","volume":"25","author":"Shintani","year":"2010","journal-title":"Microbes Environ"},{"key":"ref471","doi-asserted-by":"crossref","first-page":"186","DOI":"10.1089\/mdr.2014.0073","article-title":"Characterization of extended-spectrum beta-lactamase, carbapenemase and plasmid quinolone determinants in Klebsiella pneumoniae isolates carrying distinct types of 16s rRNA methylase genes and their association with mobile genetic elements","volume":"21","author":"Wei","year":"2015","journal-title":"Microb Drug Resist"},{"key":"ref361","doi-asserted-by":"crossref","first-page":"797","DOI":"10.1016\/S0140-6736(97)07322-4","article-title":"Quinolone resistance from a transferable plasmid","volume":"351","author":"Mart\u00ednez-Mart\u00ednez","year":"1998","journal-title":"Lancet"},{"key":"ref391","doi-asserted-by":"crossref","first-page":"711","DOI":"10.1038\/nrmicro1234","article-title":"Mechanisms of, and barriers to, horizontal gene transfer between bacteria","volume":"3","author":"Thomas","year":"2005","journal-title":"Nat Rev Microbiol"}],"container-title":["Acta Microbiologica et Immunologica Hungarica"],"original-title":[],"link":[{"URL":"https:\/\/www.akademiai.com\/doi\/full-xml\/10.1556\/030.65.2018.049","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/akjournals.com\/view\/journals\/030\/66\/2\/article-p169.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/akjournals.com\/downloadpdf\/journals\/030\/66\/2\/article-p169.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,5,3]],"date-time":"2022-05-03T00:40:12Z","timestamp":1651538412000},"score":1,"resource":{"primary":{"URL":"https:\/\/akjournals.com\/view\/journals\/030\/66\/2\/article-p169.xml"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,11,22]]},"references-count":58,"journal-issue":{"issue":"2"},"URL":"https:\/\/doi.org\/10.1556\/030.65.2018.049","relation":{},"ISSN":["1217-8950","1588-2640"],"issn-type":[{"value":"1217-8950","type":"print"},{"value":"1588-2640","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,11,22]]}}}