临床致病菌整合子检测及耐药基因盒序列分析  

Detection of class 1 integron and sequencing analysis of resistance gene(s) cassette in clinical isolates of bacteria

作　　者：石磊[1] 郑美萍[1] 肖增璜[2] 李琳[1] 邱春嫦[2] 付强[2] 苏健裕[1] 李心晖[1] 冯洁[1] 

机构地区：[1]华南理工大学轻工与食品学院 [2]暨南大学附属第一医院临床检验中心

出　　处：《中华检验医学杂志》2005年第11期1204-1206,1210,共4页Chinese Journal of Laboratory Medicine

基　　金：教育部留学回国人员科研启动基金(B7321090);广东省自然科学基金项目(04020050);广州市科技计划项目(2004J1C0161)

摘　　要：目的对临床菌株中的第一类整合子分布及其耐药基因盒的结构特征进行分析。方法应用PCR方法检测33株临床菌株中的第一类整合酶基因intI,并对intI阳性菌株整合的耐药基因进行测序及序列分析。结果33株临床菌株(100%)均为第一类整合酶基因阳性。耐药基因盒特异PCR扩增发现,29株菌得到1913bp的扩增产物,2株得到1664bp的产物,1株得到1009bp的产物,1株得到1913bp和1009bp两种不同产物。序列分析结果表明,1913bp的扩增产物携带基因盒dhfr、orfF和aadA2,1664bp的扩增产物携带基因盒aadA5和dfr17,1009bp的扩增产物携带基因盒aadA2,aadA2和aadA5均为编码对氨基糖苷类抗生素产生耐药的基因盒,dhfr和dfr17均为编码对磺胺类药物甲氧苄氨嘧啶产生耐药的基因盒;orfF为未知功能的开放阅读框。结论第一类整合子介导的耐药基因广泛存在于临床致病细菌中,提示要加强对耐药基因在细菌种属间水平转移的监测工作。Objective To investigate resistance genes in bacteria, the distribution and characterization of the class 1 integron among clinical strains were investigated. Methods The presence and genetic content of class 1 integron among 33 clinical examined by PCR and sequencing. Results Thirtythree（ 100% ）strains were positive for intI1 gene. Furthermore, intI1 -positive strains were amplified with primers of in-F and in-B which were set for amplifying the region of antibiotics resistance genes. Among 33 strains, an amplicon of 1 913 bp was yielded in 29,an amplicon of 1 664 bp was yielded in 2 isolates, an amplicn of 1 009 bp was yielded in 1 isolates, 1 isolates presented two amplicons of 1 913 and 1 009 bp. Sequencing data revealed that amplicon 1 913 bp harbored genes of dhfr,orfF and aadA2, amplicon 1 664 bp harbored genes of aadA5 and dfrl7, the amplicn of 1 009 bp harbored genes of aadA2, aadA2 and aadA5 showing aminoglycoside resistance; dhfr and dfrl7 conferring resistance to trimethoprim, orfF encoding unknown function. Conclusion Resistance gene（s） mediated by class 1 integron was extensively existed in clinical isolates of bacteria. The result stressed the need for continued surveillance of horizontal transference of antibiotic resistance gene（s） among bacteria genus.

关 键 词：临床医学 整合酶 基因序列分析 

分 类 号：R446.5[医药卫生—诊断学]