title: Conjugative transfer of resistance determinants among human and bovine Streptococcus agalactiae.
abstract: Streptococcus agalactiae (GBS) is a major source of human perinatal diseases and bovine mastitis. Erythromycin (Ery) and tetracycline (Tet) are usually employed for preventing human and bovine infections although resistance to such agents has become common among GBS strains. Ery and Tet resistance genes are usually carried by conjugative transposons (CTns) belonging to the Tn916 family, but their presence and transferability among GBS strains have not been totally explored. Here we evaluated the presence of Tet resistance genes (tetM and tetO) and CTns among Ery-resistant (Ery-R) and Ery-susceptible (Ery-S) GBS strains isolated from human and bovine sources; and analyzed the ability for transferring resistance determinants between strains from both origins. Tet resistance and int-Tn genes were more common among Ery-R when compared to Ery-S isolates. Conjugative transfer of all resistance genes detected among the GBS strains included in this study (ermA, ermB, mef, tetM and tetO), in frequencies between 1.10(-7) and 9.10(-7), was possible from bovine donor strains to human recipient strain, but not the other way around. This is, to our knowledge, the first report of in vitro conjugation of Ery and Tet resistance genes among GBS strains recovered from different hosts.
authors.affiliation: Instituto de Microbiologia Paulo de Góes Universidade Federal do Rio de Janeiro Rio de JaneiroRJ Brazil Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Tatiana Castro Abreu
authors.initials: TC
authors.lastname: Pinto
authors.affiliation: Instituto de Microbiologia Paulo de Góes Universidade Federal do Rio de Janeiro Rio de JaneiroRJ Brazil Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Natália Silva
authors.initials: NS
authors.lastname: Costa
authors.affiliation: Instituto de Microbiologia Paulo de Góes Universidade Federal do Rio de Janeiro Rio de JaneiroRJ Brazil Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Ana Beatriz de Almeida
authors.initials: AB
authors.lastname: Corrêa
authors.affiliation: Instituto de Microbiologia Paulo de Góes Universidade Federal do Rio de Janeiro Rio de JaneiroRJ Brazil Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Ivi Cristina Menezes
authors.initials: IC
authors.lastname: de Oliveira
authors.affiliation: Instituto de Microbiologia Paulo de Góes Universidade Federal do Rio de Janeiro Rio de JaneiroRJ Brazil Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Marcos Correa
authors.initials: MC
authors.lastname: de Mattos
authors.affiliation: Instituto de Microbiologia Paulo de Góes Universidade Federal do Rio de Janeiro Rio de JaneiroRJ Brazil Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Alexandre Soares
authors.initials: AS
authors.lastname: Rosado
authors.affiliation: Instituto de Microbiologia Paulo de Góes Universidade Federal do Rio de Janeiro Rio de JaneiroRJ Brazil Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Leslie Claude
authors.initials: LC
authors.lastname: Benchetrit
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002417:Cattle; D003227:Conjugation, Genetic; D004251:DNA Transposable Elements; D024881:Drug Resistance, Bacterial; D004917:Erythromycin / Q000494:pharmacology; D018014:Gene Transfer Techniques; D006801:Humans; D013290:Streptococcal Infections / Q000382:microbiology / Q000662:veterinary; D013292:Streptococcus agalactiae / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D013752:Tetracycline / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D004251:DNA Transposable Elements; D004917:Erythromycin; D013752:Tetracycline
keywords: Streptococcus agalactiae (GBS); conjugative transposons; erythromycin resistance; tetracycline resistance