Molecular epidemiology of macrolide and tetracycline resistances in commensal Gemella sp. isolates.
The epidemiologic relatedness of 29 erythromycin-resistant Gemella sp. strains from normal flora, characterized previously, were evaluated by pulsed-field gel electrophoresis (PFGE). Three isolates carried the tet(O) gene and the tet(M) gene. The msr(A) gene was found in two Gemella morbillorum strains in combination with the erm(B) or mef(E) gene. The sequences of the mef(A/E), erm(B), and msr(A) genes showed a high similarity to the corresponding sequences of other gram-positive cocci. All the strains harboring the mef(A/E) gene and the msr(D) gene possessed open reading frame 3 (ORF3)/ORF6. The 16 G. morbillorum isolates represented 15 distinct DNA profiles. Four clusters were identified (>or=80% genetic relatedness). The 12 Gemella haemolysans strains belonged to different PFGE types. The clonal diversity found suggests that horizontal transfer may be the main route through which erythromycin resistance is acquired.
Zolezzi
Paula Cerdá
PC
Department of Microbiology, Preventive Medicine and Public Health, Faculty of Medicine, University of Zaragoza, C/Domingo Miral s/n, 50009 Zaragoza, and Centro de Salud Internacional, IDIBAPS, Hospital Clinic, Barcelona, Spain.
Cepero
Pilar Goñi
PG
Ruiz
Joaquim
J
Laplana
Leticia Millán
LM
Calvo
Carmen Rubio
CR
Gómez-Lus
Rafael
R
D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D018942:Macrolides / Q000494:pharmacology*; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D010802:Phylogeny; D040141:Staphylococcaceae / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D013752:Tetracycline / Q000494:pharmacology*; D013753:Tetracycline Resistance / Q000235:genetics*
D018942:Macrolides; D013752:Tetracycline