title: Organization of the antiseptic resistance gene qacA and Tn552-related beta-lactamase genes in multidrug- resistant Staphylococcus haemolyticus strains of animal and human origins.
abstract: A part (12 kb) of a plasmid containing the beta-lactamase genes of Tn552, the disinfectant resistance gene qacA, and flanking DNA has been cloned from a Staphylococcus haemolyticus isolate and sequenced. This region was used to map the corresponding regions in six other multiresistant S. haemolyticus isolates of human and animal origin. The organizations of the genetic structures were almost identical in all isolates studied. The beta-lactamase and qacA genes from S. haemolyticus have >99.9% identities at the nucleotide level with the same genes from S. aureus, demonstrating that various staphylococcal species able to colonize animal and human hosts can exchange the genetic elements involved in resistance to antibiotics and disinfectants. The use of antibiotics and disinfectants in veterinary practice and animal husbandry may also contribute to the selection and maintenance of resistance factors among the staphylococcal species. Different parts of the 12-kb section analyzed had high degrees of nucleotide identity with regions from several other different Staphylococcus aureus plasmids. This suggests the contribution of interplasmid recombination in the evolutionary makeup of this 12-kb section involving plasmids that can intermingle between various staphylococcal species. The lateral spread of resistance genes between various staphylococcal species is probably facilitated by the generation of large multiresistance plasmids and the subsequent interspecies exchange of them.
authors.affiliation: Department of Pharmacology, Microbiology, and Food Hygiene, The Norwegian School of Veterinary Science, 0033 Oslo. MATFORSK, Norwegian Food Research Institute, N-1430 As, Norway.
authors.forename: I-L
authors.initials: IL
authors.lastname: Anthonisen
authors.forename: M
authors.initials: M
authors.lastname: Sunde
authors.forename: T M
authors.initials: TM
authors.lastname: Steinum
authors.forename: M S
authors.initials: MS
authors.lastname: Sidhu
authors.forename: H
authors.initials: H
authors.lastname: Sørum
mesh_terms: D000818:Animals; D000891:Anti-Infective Agents, Local / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics*; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D015252:Deoxyribonucleases, Type II Site-Specific / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial; D004996:Ethidium / Q000494:pharmacology; D006801:Humans; D026901:Membrane Transport Proteins / Q000235:genetics*; D009693:Nucleic Acid Hybridization; D010957:Plasmids / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013203:Staphylococcal Infections / Q000382:microbiology*; D041162:Staphylococcus haemolyticus / Q000187:drug effects* / Q000235:genetics*; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D000891:Anti-Infective Agents, Local; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D026901:Membrane Transport Proteins; C068498:qacA protein, Staphylococcus aureus; D015252:Deoxyribonucleases, Type II Site-Specific; C024400:GTYRAC-specific type II deoxyribonucleases; D001618:beta-Lactamases; C472385:beta-lactamase Tn552, Staphylococcus haemolyticus; D004996:Ethidium