Zolezzi Paula Cerdá, Cepero Pilar Goñi, Ruiz Joaquim, Laplana Leticia Millán, Calvo Carmen Rubio, Gómez-Lus Rafael
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.
Antimicrob Agents Chemother. 2007 Apr;51(4):1487-90. doi: 10.1128/AAC.01374-06. Epub 2007 Feb 5.
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.
通过脉冲场凝胶电泳（PFGE）对先前已鉴定的29株来自正常菌群的耐红霉素孪生球菌属菌株的流行病学相关性进行了评估。三株分离株携带tet（O）基因和tet（M）基因。在两株麻疹孪生球菌菌株中发现msr（A）基因，其与erm（B）或mef（E）基因同时存在。mef（A/E）、erm（B）和msr（A）基因的序列与其他革兰氏阳性球菌的相应序列高度相似。所有携带mef（A/E）基因和msr（D）基因的菌株都拥有开放阅读框3（ORF3）/ORF6。16株麻疹孪生球菌分离株代表了15种不同的DNA图谱。鉴定出四个聚类（遗传相关性≥80%）。12株溶血孪生球菌菌株属于不同的PFGE类型。所发现的克隆多样性表明水平转移可能是获得红霉素耐药性的主要途径。
