目的了解鲍曼不动杆菌临床株中Ⅰ类整合子、插入序列共同区（ISCR1）的分布情况，研究它们所携带的耐药基因。方法收集来自临床的51株多重耐药鲍曼不动杆菌，PCR检测Ⅰ类整合酶基因、Ⅰ类整合子可变区、ISCR1和ISCR1下游基因环境，DNA序列分析检测Ⅰ类整合子和ISCR1携带的耐药基因，PCR-mapping检测Ⅰ类整合子与ISCR1的关系。结果51株多重耐药鲍曼不动杆菌中Ⅰ类整合酶基因阳性45株，32株检出可变区结构， DNA序列分析显示携带aacA4-catB8-aadA1、aacC1-orfA-orfB-aadA1、blaPSE-1-aadA2-cmlA1-aadA13种形式的耐药基因盒；ISCR1阳性22株，5株检出ISCR1下游基因，DNA序列分析结果为qnrA1-ampR。PCR-mapping显示20株鲍曼不动杆菌中的ISCR1直接连接在Ⅰ类整合子3′保守区下游。结论Ⅰ类整合子、ISCR1在鲍曼不动杆菌耐药中起重要作用，且Ⅰ类整合子和ISCR1可以串联形式存在于鲍曼不动杆菌中。%Objective To investigate the distribution and the antibiotic resistance genes carried by classⅠintegron and insertion sequence common region(ISCR1)among clinical isolates of Acinetobacter baumannii. Methods Fifty-one clinical isolates of multidrug-resistant Acinetobacter baumannii were collected. Polymerase chain reaction method was used to detect the classⅠintegrase gene, variable region of classⅠintegron, ISCR1 and genes related to antibiotics resistance lo-cated downstream of ISCR1 in 51 multidrug-resistant Acinetobacter baumannii. Antibiotics resistance genes carried by classⅠintegron and ISCR1 were performed by DNA sequencing. The relationship between classⅠintegron and ISCR1 was detected by PCR-mapping. Results Among 51 multidrug-resistant Acinetobacter baumannii isolates, 45 strains were found con-taining classⅠintegrase genes, 32 strains were found containing variable regions. Sequencing results showed that the gene cassette arrays were aacA4-catB8-aadA1, aacC1-orfA-orf-B-aadA1 and blaPSE-1-aadA2-cmlA1-aadA1. Twenty-two strains were found containing ISCR1 and 5 strains were found containing resistance genes located downstream of ISCR1. DNA sequencing results showed the resistant gene of qnrA1-ampR. The results of PCR-mapping showed that ISCR1 located directly downstream of 3' conserved segment of classⅠintegron in 20 Acinetobacter baumannii strains. Conclusion ClassⅠintegron and ISCR1 play an important role in mechanisms of drug resistance of Acinetobacter baumannii. ClassⅠintegron and ISCR1 could connect in series in Acinetobacter baumannii.
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