肺炎克雷伯菌质粒编码的AmpC酶和超广谱β-内酰胺酶的表型和基因型分析  

Phenotype and Genotype of Plasmid-encoded AmpC and Extended Spectrum Beta-lactamases in Klebsiella pneumoniae

作　　者：沈定霞[1] 罗燕萍[1] 曹敬荣[1] 周光[1] 田芳[1] 

机构地区：[1]解放军总医院,北京100853

出　　处：《中华医院感染学杂志》2007年第6期639-642,共4页Chinese Journal of Nosocomiology

基　　金：全军"十一五"基金课题(06MA294)

摘　　要：目的研究肺炎克雷伯菌质粒编码的AmpC酶和超广谱β-内酰胺酶(ESBLs)的表型和基因型。方法利用3-氨基苯酚硼酸及ESBLs确认试验检测AmpC酶与ESBLs表型,接合转移试验了解质粒在细菌间的传递;通过质粒的提取、纯化,PCR反应及序列分析,研究肺炎克雷伯菌质粒携带的ampC基因和ESBLs基因类型。结果从肺炎克雷伯菌中获得1条约15 kb大小的质粒,此质粒可通过接合转移方式将耐药性传递至大肠埃希菌,以从肺炎克雷伯菌及接合转移后的接合子细菌中,提取的质粒为模板,均可扩增出DHA型ampC基因及SHV型ESBLs基因,序列分析进一步证实ampC及ESBLs基因型分别为DHA-1型及SHV-12型。结论从肺炎克雷伯菌可转移的质粒中,检测到DHA-1型ampC基因及SHV-12型ESBLs基因。OBJECTIVE To investigate the phenotype and genotype of plasmid-encoded AmpC and extended spectrum beta-lactamases in Klebsiella pneumoniae. METHODS 3-Aminophenylboronic acid （APB） test and ESBLs confirmatory test were used for phenotypic detection of AmpC and ESBLs. Conjugation was conducted in order to understand the spread of plasmid in bacteria. The size and genotype of ampC and ESBL genes were studied by extraction and purification of plasmid, PCR and sequencing analysis. RESULTS A plasmid of about 15kb was extracted from K. pneumoniae. This plasmid carrying resistance genes to antibiotics could be spread from K. pneumoniae to recipient Escherichia coli NK5449 through conjugation. DHA-type ampC gene and SHV-type ESBLs gene could be amplified from plasmids extracted from both K. pneumoniae and its conjugant in E. coli, they were DHA-1 ampC gene and SHV-12 ESBLs gene confirmed by sequencing analysis. CONCLUSIONS DHA-1 ampC gene and SHV-12 ESBLs gene are detected from the plasmid of K. pneumoniae.

关 键 词：肺炎克雷伯菌 质粒 超广谱Β-内酰胺酶 AMPC酶 基因型 

分 类 号：R378.991[医药卫生—病原生物学]