不动杆菌中整合子及其与耐药性的关系研究

目的了解不动杆菌属中的整合子及其与耐药性的关系。方法采用多重聚合酶链反应(PCR)检测整合子;采用ERIC-PCR检测其同源性;用联合限制性片段多态性分析检测整合子基因盒。结果 122株不动杆菌中53株包含有1类整合子,而这53株中只有40株扩增出耐药基因盒,其有4种基因盒:arr-3-aacA4(几种不同的菌株中的24株)、aacC1-orfP-orfQ-aadA1a(11株,可能所有是相同的菌株)、aacA4-catB8-aadA1(2株)和dfrⅦ(1株)。结论整合子和耐碳青霉烯类缺少相关性;我国的整合子基因盒出现地域化,而arr3基因我国成为一个特征;arr3-aacA4基因盒在不动杆菌菌株中存在明显的水平基因转移,说明整合子基因盒在不动杆菌中存在明显的水平基因转移。

Study on the integrons in acinetobacter and the relationship with antibiotic resistance

Objective To investigate the integrons in acinetobacter and the relationship with antibiotic resist- ance. Methods Class 1,2and 3 integrons were detected by multiplex PCR. The homology among different strains was tested by enterobacterial repetitive intergenic consensus-PCR（ERIC-PCR） method; Restriction fragment length polymorphism（RFLP） was used to detect the integrons gene cassettes. Results 53 out of the 122 isolates contained class I integrons,and gene cassette arrays were amplified from 40 of the integrons containing isolates while four different cassette arrays were identified, which include arv3 aacA4 （24 isolates of several unrelated strains）, aacCl-orfP-orfQ aadAla（ll isolates,probably all the same strains）, （2 isolates） ,and dfrⅧ （1 isolates）. Conclusion There are lack of correlation between integron content and carbapenem-resistance; The arrays described in China appear to be regionally loculized; and the apparent importance of the art3 gene in a number of arrays is a distinctive feature in China. The horizontal gene transfer is clearly evident among the acinetobacter SPP. collected in this study.