【摘要】 目的研究革兰阴性杆菌产β-内酰胺酶的基因型。方法收集北京大学人民医院12株革兰阴性杆菌,用VITEK-2系统进行鉴定和药敏检测,对多种β内酰胺酶基因进行聚合酶链反应(PCR)扩增,耐药基因与pGEM-3zf载体连接转化至大肠埃希菌DH5α,筛选、鉴定阳性克隆后进行序列分析。结果12株菌检测出CTX-M型、TEM型、SHV型、OXA型、PER型和IMP型耐药基因,其中1株鲍曼不动杆菌同时携带OXA型和PER型耐药基因。2株大肠埃希菌的耐药基因分别在CTX-M-14的基础上发生了1个位点的突变。结论细菌携带一种或多种耐药基因导致多重耐药,基因突变可导致新的基因型产生。鲍曼不动杆菌产金属碳青霉烯酶或丝氨酸碳青霉烯酶对亚胺培南耐药。更多还原

【Abstract】 [Objective] To survey the types of β-lactamase genes in gram-negative bacteria. [Methods] Twelve strains of gram-negative came from Peking University People Hospital. VITEK-2 system was used to identify bacteria strains and to detect susceptibility to drugs. Several β-lactamase genes were amplified using PCR method, then the segments of β-lactamase gene were ligated with pGEM-3zf, transferred to DH5α.Sequence of β-lactamase genes were analyzed among the positive clones. [Result] Twelve strains were positive for CTX-M, TEM, SHV, OXA, PER and IMP type drug-resistant genes. One strain of Acinetobacter baumannii carries both OXA and PER gene. Two variant sequences of CTX-M-14 had been discovered in one site separately from two strains of Escherichia coli. [Conclusion] Multi-drug resistant can result from bacteria carrying one or more drug-resistant genes. Gene mutation can produce new gene types. Acinetobacter baumannii expresses metalo-carbapenemase or serine-carbapenemase to resist Emipenem.更多还原