RESUMO
OBJECTIVES: The aims of this study were to identify small staphylococcal plasmids that carry either the trimethoprim resistance gene dfrK or the apramycin resistance gene apmA and analyse them for their structure and organization with regard to their potential role as precursors of large multiresistance plasmids that carry these genes. METHODS: Trimethoprim- or apramycin-resistant staphylococci from the strain collections of the two participating institutions were investigated for the presence of plasmid-borne dfrK or apmA genes. The dfrK- or apmA-carrying plasmids were sequenced completely and compared with sequences deposited in the databases. RESULTS: Two small plasmids, the 4957 bp dfrK-carrying plasmid pKKS966 from porcine Staphylococcus hyicus subsp. hyicus and the 4809 bp apmA-carrying plasmid pKKS49 from porcine methicillin-resistant Staphylococcus aureus were identified. Structural analysis revealed that both plasmids had a similar organization, comprising a single resistance gene (dfrK or apmA), a plasmid replication gene (rep) and three partly overlapping genes for mobilization proteins (mobA, mobB and mobC). Comparisons showed 71%-82% amino acid identity between the Rep and Mob proteins of these two plasmids; however, distinctly lesser percentages of identity to Rep and Mob proteins of staphylococci and other bacteria deposited in the databases were detected. CONCLUSIONS: Both plasmids, pKKS966 and pKKS49, appeared not to be typical staphylococcal plasmids. The homology to larger plasmids that harbour the genes apmA and/or dfrK was limited to these resistance genes and their immediate upstream and downstream regions and thus suggested that these small plasmids were not integrated into larger plasmids.
Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Nebramicina/análogos & derivados , Plasmídeos , Staphylococcus/efeitos dos fármacos , Staphylococcus/genética , Trimetoprima/farmacologia , Animais , DNA Bacteriano/química , DNA Bacteriano/genética , Ordem dos Genes , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Dados de Sequência Molecular , Nebramicina/farmacologia , Análise de Sequência de DNA , Homologia de Sequência , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/veterináriaAssuntos
Transportadores de Cassetes de Ligação de ATP/genética , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla/genética , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Plasmídeos/genética , Doenças dos Suínos/microbiologia , Animais , Diterpenos/farmacologia , Feminino , Lincosamidas/farmacologia , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Compostos Policíclicos , Recombinação Genética , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/veterinária , Estreptogramina Grupo A/farmacologia , Suínos , Zoonoses/microbiologia , PleuromutilinasRESUMO
BACKGROUND: The A, B, and AB feline blood types are recognized worldwide and their frequencies vary geographically and among breeds. Frequencies of feline blood types have been reported previously from northern Portugal; however, they are unknown in other parts of the country. OBJECTIVES: This 13-year retrospective study was undertaken to determine the frequency of feline blood types in domestic shorthair (DSH) cats from the Lisbon area of central Portugal. METHODS: Blood samples were obtained at the Veterinary Teaching Hospital of the Technical University of Lisbon and its Veterinary Blood Bank and at several veterinary clinics in the Lisbon area. Blood-typing was performed by the classical agglutination assay or using a cartridge assay. RESULTS: The study population comprised 515 DSH cats of both sexes and various ages. Frequencies of blood types A, B, and AB were 97.5%, 2.1%, and 0.4%, respectively. CONCLUSION: As in other parts of the world, this study showed a clear predominance of type-A cats in the Lisbon area of Portugal.