title: Resistance determinants and their association with different transposons in the antibiotic-resistant Streptococcus pneumoniae.
abstract: Multiple resistance of Streptococcus pneumoniae is generally associated with their unique recombination-mediated genetic plasticity and possessing the mobile genetic elements. The aim of our study was to detect antibiotic resistance determinants and conjugative transposons in 138 antibiotic-resistant pneumococcal strains isolated from nasopharynx of healthy young children from Lublin, Poland. These strains resistant to tetracycline and/or to chloramphenicol/erythromycin/clindamycin were tested by PCR using the specific genes as markers. The presence of Tn916 family transposons, carrying tet(M) and int/xisTn916, was observed in all of the tested strains. Tn916 was detected in 16 strains resistant only to tetracycline. Tn6002 and Tn3872-related element were found among 99 erm(B)-carrying strains (83.8% and 3.0%, resp.). Eight strains harbouring mef(E) and erm(B) genes were detected, suggesting the presence of Tn2010 and Tn2017 transposons. Among 101 chloramphenicol-resistant strains, two variants of Tn5252-related transposon were distinguished depending on the presence of int/xis5252 genes specific for cat gene-containing Tn5252 (75.2% of strains) or int Sp23FST81 gene, specific for cat-containing ICESp23FST81 element (24.8% of strains). In 6 strains Tn916-like and Tn5252-like elements formed a Tn5253-like structure. Besides clonal dissemination of resistant strains of pneumococci in the population, horizontal transfer of conjugative transposons is an important factor of the high prevalence of antibiotic resistance.
authors.affiliation: Department of Pharmaceutical Microbiology, Medical University of Lublin, Chodzki 1, 20-093 Lublin, Poland.
authors.forename: Izabela
authors.initials: I
authors.lastname: Korona-Glowniak
authors.affiliation: Department of Pharmaceutical Microbiology, Medical University of Lublin, Chodzki 1, 20-093 Lublin, Poland.
authors.forename: Radoslaw
authors.initials: R
authors.lastname: Siwiec
authors.affiliation: Department of Pharmaceutical Microbiology, Medical University of Lublin, Chodzki 1, 20-093 Lublin, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Malm
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004251:DNA Transposable Elements / Q000235:genetics*; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D013296:Streptococcus pneumoniae / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D004251:DNA Transposable Elements