title: Genetic diversity and antimicrobial resistance in Streptococcus agalactiae strains recovered from female carriers in the Bucharest area.
abstract: For the first time, we used multilocus sequence typing (MLST) to understand how Romanian group B streptococcus (GBS) strains fit into the global GBS population structure. Colonising isolates recovered from adult human females were tested for antibiotic resistance, were molecularly serotyped based on the capsular polysaccharide synthesis (cps) gene cluster and further characterised using a set of molecular markers (surface protein genes, pilus-encoded islands and mobile genetic elements inserted in the scpB-lmb intergenic region). Pulsed-field gel electrophoresis was used to complement the MLST clonal distribution pattern of selected strains. Among the 55 strains assigned to six cps types (Ia, Ib, II-V), 18 sequence types (STs) were identified by MLST. Five STs represented new entries to the MLST database. The prevalent STs were ST-1, ST-17, ST-19 and ST-28. Twenty molecular marker profiles were identified. The most common profiles (rib+GBSi1+PI-1, rib+GBSi1+PI-1, PI-2b and alp2/3+PI-1, PI-2a) were associated with the cps III/ST-17 and cps V/ST-1 strains. A cluster of fluoroquinolone-resistant strains was detected among the cps V/ST-19 members; these strains shared alp1 and IS1548 and carried PI-1, PI-2a or both. Our results support the usefulness of implementing an integrated genotyping system at the reference laboratory level to obtain the reliable data required to make comparisons between countries.
authors.affiliation: Molecular Epidemiology Laboratory, Cantacuzino National Institute of Research/Development for Microbiology and Immunology, Bucharest, Romania.
authors.forename: Codruţa-Romaniţa
authors.initials: CR
authors.lastname: Usein
authors.affiliation: Molecular Epidemiology Laboratory, Cantacuzino National Institute of Research/Development for Microbiology and Immunology, Bucharest, Romania.
authors.forename: Mădălina
authors.initials: M
authors.lastname: Militaru
authors.affiliation: Synevo Laboratories, Judetul Ilfov, Romania.
authors.forename: Violeta
authors.initials: V
authors.lastname: Cristea
authors.affiliation: Molecular Epidemiology Laboratory, Cantacuzino National Institute of Research/Development for Microbiology and Immunology, Bucharest, Romania.
authors.forename: Monica
authors.initials: M
authors.lastname: Străuţ
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002353:Carrier State / Q000382:microbiology*; D004269:DNA, Bacterial / Q000235:genetics*; D021901:DNA, Intergenic / Q000032:analysis; D030561:Databases, Nucleic Acid; D052978:Disk Diffusion Antimicrobial Tests; D004352:Drug Resistance, Microbial / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D010861:Fimbriae, Bacterial / Q000502:physiology; D005798:Genes, Bacterial; D014644:Genetic Variation; D006801:Humans; D020071:Interspersed Repetitive Sequences / Q000502:physiology; D008565:Membrane Proteins / Q000235:genetics; D058885:Multilocus Sequence Typing; D012383:Romania; D013292:Streptococcus agalactiae / Q000187:drug effects / Q000235:genetics*; D014626:Vaginal Smears; D014774:Virulence
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D021901:DNA, Intergenic; D008565:Membrane Proteins