title: Analysis of mutations in DNA gyrase and topoisomerase IV of Ureaplasma urealyticum and Ureaplasma parvum serovars resistant to fluoroquinolones.
abstract: This study aims to determine the prevalence of fluoroquinolone resistance of Ureaplasma biovars and serovars isolated from urogenital clinical samples and determine the underlying molecular mechanism for quinolone resistance for all resistant isolates. Of 105 samples confirmed as positive for U. urealyticum/U. parvum, 85 were resistant to quinolones by the Mycoplasma-IST2 kit. However, only 43 out of 85 quinolone resistant isolates had amino acid substitutions in GyrA, GyrB, ParC and ParE proteins underlining that this assay have mis-identified as fluoroquinolone resistant 42 isolates. The known ParC E87K and ParC S83L mutations were found in 1 and 10 isolates, respectively. An original mutation of ureaplasmal ParC (E87Q, 1 isolate) was found. Furthermore, we found a ParE R448K mutation in one isolate, already described. Among the additional alterations detected, the most prevalent mutation found was L176F in GyrA protein in 18 isolates with single infection and in 3 isolates with mixed ureaplasma infections. Mutations in GyrB (E502Q, 4 isolates), ParE (Q412K, Q412P, Q412T, 3 independent isolates), whose role is unknown, were also found. Other sporadic mutations in the four genes were identified. This investigation is the result of monitoring the data for molecular fluoroquinone resistance in Ureaplasma spp. in Italy. Resulting that this acquired resistance is high and that continued local epidemiological studies are essential to monitor and document their antimicrobial resistance trends.
authors.affiliation: Institute of Microbiology, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Piccinelli
authors.affiliation: Institute of Microbiology, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy.
authors.forename: Franco
authors.initials: F
authors.lastname: Gargiulo
authors.affiliation: Institute of Microbiology, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Biscaro
authors.affiliation: Institute of Microbiology, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Caccuri
authors.affiliation: Institute of Microbiology, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy.
authors.forename: Arnaldo
authors.initials: A
authors.lastname: Caruso
authors.affiliation: Institute of Microbiology, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy. Electronic address: maria.defrancesco@unibs.it.
authors.forename: Maria Antonia
authors.initials: MA
authors.lastname: De Francesco
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics*; D027081:DNA Gyrase / Q000235:genetics*; D027101:DNA Topoisomerase IV / Q000235:genetics*; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D024841:Fluoroquinolones / Q000494:pharmacology*; D006801:Humans; D009154:Mutation / Q000235:genetics*; D014509:Ureaplasma / Q000187:drug effects / Q000201:enzymology / Q000235:genetics; D016869:Ureaplasma Infections / Q000382:microbiology; D016990:Ureaplasma urealyticum / Q000187:drug effects / Q000201:enzymology / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D024841:Fluoroquinolones; D027101:DNA Topoisomerase IV; D027081:DNA Gyrase
keywords: Antibiotic resistance; QRDR; Serovars