导致氨基糖苷类药物双圈耐药型鲍曼不动杆菌的相关携带基因研究  

A study on carrying genes relevant to double-circle resistance to aminoglycoside antibiotic in Acinetobacter baumannii

作　　者：张晓文[1,2] 邵海枫[2] 王卫萍[2] 李晓军[2] 

机构地区：[1]南京师范大学生命科学学院,南京210046 [2]南京军区南京总医院解放军临床检验医学研究所,南京210002

出　　处：《临床检验杂志》2011年第1期19-21,共3页Chinese Journal of Clinical Laboratory Science

基　　金：江苏省医学重点学科基金资助项目(苏卫科教[2001]34)

摘　　要：目的探讨在K-B法药物敏感试验中对氨基糖苷类抗菌药物双圈耐药的鲍曼不动杆菌耐药基因携带状况及药物诱导对耐药基因mRNA表达量的影响。方法收集42株携带Ⅰ类整合子酶基因的鲍曼不动杆菌;PCR法扩增其整合子可变区;联合RFLP和DNA测序技术分析可变区耐药基因;用RT-PCR的方法分析药物诱导前后细菌耐药基因表达量。结果 90.4%(38/42)的整合子阳性菌株可变区扩增片段大小为2300bp左右。RFLP分型和DNA测序结果表明,整合子可变区携带的基因盒为aacA4-catB-aadA1。RT-PCR结果显示经阿米卡星诱导后细菌aacA4基因mRNA表达量显著上升。结论氨基糖苷类药物双圈耐药型菌株的Ⅰ类整合子中主要携带氨基糖苷类耐药基因,双圈现象可能与整合子携带的耐药基因诱导型表达有关。Objective To explore the presence of resistance genes in Acinetobacter baumannii which showed double-circle resistant to aminoglycoside antibiotic by detection with K-B methods,and analyze the expression levels of resistance gene mRNA among the strains induced and non-induced by amikacin.Methods A total of 42 strains of class I integron-positive Acinetobacter baumannii was collected,and the variable region was analyzed by PCR and RFLP.DNA sequencing was used to identify the gene cassettes of variable integrons.The genes expressions in drug-induced and non-induced strains were measured by PT-PCR respectively.Results Of the integron-positive strains 90.4%（38/42） contained variable region,and the size of the amplicons was about 2 300 bp.The results of RFLP and DNA sequencing showed that the cassettes carried in the variable region of integrons were aacA4-catB-aadA1.PT-PCR revealed that the expression level of aacA4 gene mRNA was significantly up-regulated when the strains were induced by amikacin.Conclusion The integrons class I in double-circle strains may mainly carry the genes resistant to aminoglycoside.The phenomenon of double-circle may associate with the inducible expressed genes.

关 键 词：鲍曼不动杆菌 氨基糖苷类药物 双圈耐药 RT-PCR 

分 类 号：R446.5[医药卫生—诊断学]