Methods: The acrB gene of Salmonella typhi 275,OM2 and 182 were identified by PCR with the primers designed from Genebank(No. AL627267) and the DNA fragments were sequenced to confirm the existence of acrAB gene.

• 方法 :参考伤寒沙门菌基因库序列 (No .；AL6 2 72 6 7)设计引物；对伤寒沙门菌 2 75、OM 2、182PCR扩增acrB基因；以证实acrAB外排系统的存在；并对 3株伤寒沙门菌扩增所得的acrB测序并分析其序列。