【摘要】 为研究大肠杆菌ESBLs类耐药基因和HPI基因在环境中的污染状况及相关性,采用双重PCR对大肠杆菌中HPI基因irp1、irp2、fyuA和产超广谱β-内酰胺酶(ESBLs)耐药基因TEM、SHV进行了检测分析,选择irp2缺失株对两类基因的相关性进行了分析。37株大肠杆菌的检测结果显示,TEM、SHV耐药基因的阳性率分别为94.5%、56.8%;irp1+TEM、irp1+SHV、irp2+TEM、irp2+SHV、fyuA+TEM、fyuA+SHV基因的阳性率分别为13.5%、13.5%、21.6%、21.6%、16.2%、16.2%。从大肠杆菌中扩增出118、132、799、414、948bp的特异性目的条带,而从甲型副伤寒沙门氏菌、绿脓假单胞菌、肺炎克雷伯氏菌中则不能扩增出上述特异性条带。灵敏度试验表明,该反应体系的检测灵敏度为1.5×103 CFU/mL。irp2缺失株试验表明,irp2中仍能检测出TEM、SHV基因。上述结果表明,采用双重PCR能特异地从大肠杆菌中检测出β-内酰胺类耐药基因和HPI基因,且两类基因间无明显相关性。更多还原

【Abstract】 The pollution status and correlation were studied on Escherichia coli with the extended spectrum β-lactamases(ESBLs) class of resistance genes and HPI genes in the environment.Duplex PCR method was used to detect and analyse irp1,irp2 and fyuA genes of high pathogenicity island(HPI) and ESBLs resistance genes TEM and SHV,and to select an irp2 deficient strain to analysize the correlation of two types genes. The test results with 37 E.coli strains showed that TEM and SHV resistance gene positive rate was 94.5% and 56.8%,respectively. The positive rates of irp1+TEM,irp1+SHV,irp2+TEM,irp2+SHV,fyuA+TEM and fyuA+SHV gene were 13.5%,13.5%,21.6%,21.6%,16.2% and 16.2%,respectively. The specific target in a size of 118,132,799,414 or 948 bp was amplified from E.coli,but not from Salmonella paratyphi A,Pseudomonas aeruginosa and Klebsiella pneumoniae. The detection limit of genomic DNA by the duplex PCR was 1.5×103 CFU/mL.The irp2 deficient strains test showed that the TEM and SHV genes were still be detected.ESBLs resistance gene and HPI gene were specifically detected by duplex PCR method,and the deficient strain test confirmed no significant correlation between the two types of genes.更多还原