产ESBLs并高产AmpC酶肺炎克雷伯氏杆菌中整合子的基因研究

Study of Klebsiella pneumoniae on integron gene of ESBLs and AmpC-producing strains

目的 :观察 4株从临床分离产超广谱内 β内酰胺酶 (ESBLs)及AmpC酶肺炎克雷伯氏杆菌的多重耐药情况 ,分析其中整合子的存在 ,对整合子的特性进行研究 ,探讨整合子基因盒表达对肺炎克雷伯杆菌耐药表型的影响。方法 :采用微量稀释法测定复方新诺明等 15种抗菌药物对细菌的最低抑菌浓度 (MIC)。PCR技术检测整合子基因 ,DNA测序研究整合子插入耐药基因盒情况。结果 :这 4株菌对多种抗菌素耐药。其中 1株存在整合子 (扩增片段 2 0 0 0bp左右 ) ,携有dhfrXII和aadA2基因。结论 :4株菌中仅 1株存在整合子结构 ,尽管产ESBLs和AmpC酶基因未位于整合子的基因盒上 ,但整合子参与多重耐药的产生。

AIM: To observe multidrug resistance character of ESBLs and AmpC producing isolated form Klebsiella pneumoniae in clinic, to analyze the existence and character of integron and to investigate the express of gene box involve drug resistance phenotypic. METHODS: MIC of the 4 strains was examined by micro dilution method. Integron gene was determined by PCR assay with integron specific primer, and DNA sequencing was used for analyzing resistance related gene cassette. RESULTS: The 4 strains were multidrug resistance. The integron was detected in one strain of them, which carried aadA2 and dhfrXII gene. CONCLUSION: Though there is not the genes box of producing ESBLs and AmpC, integron involves in the form of multidrug resistance.