【摘要】 目的 :分析临床大肠埃希菌和肺炎克雷伯菌中超广谱 β 内酰胺酶的基因型分布以及产ESBLs细菌中头孢菌素酶的存在情况。方法 :质粒接合实验分析耐药性转移 ,根据超广谱β 内酰胺酶和头孢菌素酶各种已知基因序列设计引物 ,进行聚合酶链反应分析 ,确定超广谱β 内酰胺酶的基因型分布以及头孢菌素酶基因。 结果 :80 .4 %的菌株质粒接合实验成功 ,66%的菌株为TEM基因型 ,1 4 %的菌株为SHV基因型 ,1 0 %的菌株为CTX M型。 2株菌同时存在AmpC酶。TEM阳性的大肠埃希菌RAPD带型呈多样性。 结论 :临床分离的大肠埃希菌和肺炎克雷伯菌耐药性可以发生转移 ,ESBLs以TEM基因型为主 ,部分菌株为SHV、CTX M型。同一菌株内可以产生 2种不同基因型的超广谱β 内酰胺酶。产ESBL菌株不是以细菌克隆播散为主更多还原

【Abstract】 Objective:To investigate genotypes of extended-spectrum β-lactamases and ampC co-existence in clinical isolates K.pneumonia and E.coli.Methods:Antibiotic resistance transferability was analylized by conjugation experiments.Genotypes of ESBLs and AmpC were determined by polymerase chain reaction with type-specific primer including TEM SHV CTX-M and AmpC.Results:Transconjugants were gained from 80.4% of ESBLs-producing isolates.66% of isolate were TEM type ESBLs. 14% and 10% were SHV,CTX-M type positive respectively.2 stains showed AmpC genotype positive.Conclusion:TEM-type ESBLs are the main genotypes in clinical ESBL-producing isolates. The different genotypes of ESBLs can coexist in same strain. Most ESBLs-producing isolates are not due mainly to the clonal spread of a few epidemic strains.更多还原