Staphylococcus epidermidis strains are diverse in their pathogenicity; some are invasive and cause seri-ous nosocomial infections, whereas others are non-pathogenic commensal organisms, To analyse the implications of different virulence factors in Staphylo-coccus epidermidis infections, the complete genome of Staphylococcus epidermidis strain ATCC 12228, a non-biofilm forming, non-infection associated strain used for detection of residual antibiotics in food prod-ucts, was sequenced, This strain showed low viru-lence by mouse and rat experimental infections, The genome consists of a single 2499 279 bp chromosome and six plasmids. The chromosomal G+C content is 32.1% and 2419 protein coding sequences (CDS) are predicted, among which 230 are putative novel genes. Compared to the virulence factors in Staphylococcus aureus, aside from δ-haemolysin and 13-haemolysin, other toxin genes were not found. In contrast, the majority of adbesin genes are intact in ATCC 12228. Most strikingly, the ica operon coding for the enzymes synthesizing interbacterial cellular polysaccharide is missing in ATCC 12228 and rearrangements of adja-cent genes are shown. No mec genes, IS256, IS257, were found in ATCC 12228. It is suggested that the absence of the ica operon is a genetic marker in com-mensal Staphylococcus epidermidis strains which are less likely to become invasive.

目的 构建汉坦病毒浙37（Z37）株包膜糖蛋白基因G1、G2真核表达质粒，并在真核细胞中表达。方法 根据Z37M基因序列设计6条引物，分别以质粒pGEMZ37、pCUMZ37为模板，通过聚合酶链反应（PCR）获得G1及G2片段。将G1、G2片段经BamHⅠ、XhoⅠ双酶切后插入至真核表达载体pcDNA3.1（+），经酶切鉴定，并测序证实。以磷酸钙沉淀法分别将重组质粒转染COS27细胞，用间接免疫荧光法（IFA）检测瞬时表达的蛋白。结果 获得分别含有编码汉坦病毒（HV）Z37株包膜糖蛋白G1、G2基因的重组质粒pcDNA3.12G1、pcDNA3.12G2；在转染的COS27细胞内，用IFA可检测到细胞内有特异性荧光。结论 成功地构建了HVZ37株包膜糖蛋白G1、G2基因真核表达载体，并可在COS27细胞中瞬时表达。