铜绿假单胞菌质粒型AmpC酶DHA基因的发现

Detection of Plasmid Type AmpC β-Lactamase DHA Gene in Pseudomonas aeruginosa

目的测定35株同时耐头孢他啶、头孢噻肟、头孢西丁、氨曲南铜绿假单胞菌质粒型AmpC酶DHA。 方法 用PCR法对铜绿假单胞菌质粒型AmpC酶DHA基因进行检测,并对阳性产物作PCR产物直接DNA测 序。结果35株铜绿假单胞菌DHA基因扩增结果2株呈阳性,其中1株测得序列为DHA-Ⅰ型。结论表明我 国同时耐头孢他啶、头孢噻肟、头孢西丁、氨曲南铜绿假单胞菌也已获得DHA基因,AmpC酶DHA基因可通过 转化、接合等方式转移给其他同种或不同种菌且易于传播,因此加强监控以防DHA基因在国内某些地区的革兰 阴性菌中流行。

OBJECTIVE To analyze plasmid type AmpC β-lactamase DHA gene in 35 strains of Pseudomonas aerug-inosa simultaneousy resistant to cefazidime, cefotaxime, cefoxitine and aztreonam. METHODS P. aeruginosa plasmid type AmpC β-lactamase DHA gene was detected by PCR, the positive strains as PCR product were directly se-quenced subsequently. RESULTS It was indicated that the two P. aeruginosa strains DHA genes were positive in all 35 strains, one of them was sequenced as DHA- Ⅰ type. CONCLUSIONS The P. aeruginosastrains simultaneous resistant to cefazidime, cefotaxime, cefoxitine and aztreonam have gained DHA gene in our country, plasmid type AmpC β-lactamase DHA gene can be transferred in homogeneity or in different genera of bacteria by transforming or integrating and easy to be transferred, the intensive attention should be paid to avoid DHA gene being prevalent in Gram-positive bacteria in some areas.