title: Characterisation of levofloxacin-resistant clinical isolates of Streptococcus pyogenes in Bilbao, Spain.
abstract: The resistance mechanisms and clonal relationship were determined for two Streptococcus pyogenes isolates with high-level resistance to levofloxacin as well as to other fluoroquinolones. DNA amplification and sequencing revealed a serine-81-->phenylalanine substitution in GyrA and a double substitution in ParC of serine-79-->phenylalanine and aspartic acid-91-->asparagine. Pulsed-field gel electrophoresis analysis and emm typing determined that both isolates were emm type 28 and were genetically indistinguishable.
authors.affiliation: Departamento de Inmunología, Microbiología y Parasitología, Facultad de Farmacia, Universidad del País Vasco, Paseo de la Universidad 7, 01006 Vitoria-Gasteiz, Spain. rodrigo.alonso@ehu.es
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Alonso
authors.forename: Estibaliz
authors.initials: E
authors.lastname: Mateo
authors.forename: Guillermo
authors.initials: G
authors.lastname: Ezpeleta
authors.forename: Ramón
authors.initials: R
authors.lastname: Cisterna
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D006801:Humans; D064704:Levofloxacin; D008297:Male; D015242:Ofloxacin / Q000494:pharmacology*; D013030:Spain; D013290:Streptococcal Infections / Q000235:genetics / Q000382:microbiology*; D013297:Streptococcus pyogenes / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D064704:Levofloxacin; D015242:Ofloxacin