食品中沙门菌整合子与耐药性关系

目的 研究食品中沙门菌的整合子携带情况及整合子与耐药性之间的关系。方法PCR检测细菌总DNA中1，2，3类整合酶基因，确定细菌携带整合子的情况。整合子阳性菌株进一步检测整合子的可变区，分析插入基因盒的序列。结果69株沙门菌中25株携带1类整合子。集中分布在对4种以上抗生索耐药的菌株中。插入基因盒主要是dfr（甲氧氨嘧啶）和aadA（氨基糖甙类）基因盒，各种基因盒组合中最常见的是dfrl-aadA1。结论细菌的多重耐药性与整合子携带高度一致。

Relationship between integrons and antibiotic resistance of Salmonella isolated from food

Objective To investigate the relationship between antibiotic tesistance of Salmonella spp strains isolated from food and the integrons they harbored.Methods PCR amplifying intI gene and the variable region between the conserved segments(CS-PCR)were performed for class?1,class?2,and class?3 integron.And the integron content of every isolate was characterized by restriction fragment length polymorphisms(RFLP) analysis and sequencing.Results 25 of 69 isolates were identified as being positive for integrase 1 gene in the total DNA.Most of the integron-positive strains were resistant to more than 4 antibiotics.Most of the gene cassettes integrated in the integrons conferred resistant against trimethoprim and streptomycin-spectinomycin,and the integrons with the dfr?1-aadA?1 gene cassettes combination were predominant.Conclusion There is a good correlation between integroncarrying and the antibiotic resistance of Salmonella spp strains isolated from food.