CAJ | 학술논문

目的通过对90株多重耐药革兰阴性菌携带的整合子及耐药基因盒类型的检测,探讨整合子、基因盒与耐药表型的相关性.方法采用PCR法扩增90株革兰阴性菌Ⅰ、Ⅱ、Ⅲ类整合子及整合子阳性菌株的可变区,测序分析整合子可变区耐药基因盒的类型;药敏试验检测整合子阳性菌株与阴性菌株的耐药率.结果 90株多重耐药革兰阴性菌中整合子检出率为81.1％ (73/90),其中有Ⅰ类整合子70株,Ⅱ类整合子3株,未检测出Ⅲ类整合子.Ⅰ类整合子可变区扩增片段介于730 ～ 3300 bp,GenBank数据库BLAST分析,检测到8种整合子基因盒谱,分别为aadB 11株、aac(6’)-Ⅱ7株、aadA5 10株、dfrA17-aadA5 14株、dfrA12-OrfF-aadA2 1株、aacA4-catB8-aadA1 24株、aacC1-OrfA-OrfB-aadA1 3株与catB3-aadB-dhfrV-aacA4-nit-nit2 1株,其中catB3-aadB-dhfrV-aacA4-nit1-nit2是一种新型的耐药基因盒组合形式;Ⅱ类整合子可变区片段为1600 bp,3株均携带sat2-aadA1基因盒.药敏试验表明整合子阳性菌株对氨基糖苷类和磺胺类药物耐药率高,与整合子可变区耐药基因盒的结果相符;阳性菌株对阿米卡星较为敏感,耐药率为32.9％(24/73);另外所有菌株对多数β-内酰胺酶类药物耐药率≥80％.结论多重耐药革兰阴性菌Ⅰ类整合子携带率较高,且菌株耐药表型与其整合子可变区耐药基因盒的类型有相关性.
목적 통과대90주다중내약혁란음성균휴대적정합자급내약기인합류형적검측,탐토정합자、기인합여내약표형적상관성.방법 채용PCR법확증90주혁란음성균Ⅰ、Ⅱ、Ⅲ류정합자급정합자양성균주적가변구,측서분석정합자가변구내약기인합적류형;약민시험검측정합자양성균주여음성균주적내약솔.결과 90주다중내약혁란음성균중정합자검출솔위81.1％ (73/90),기중유Ⅰ류정합자70주,Ⅱ류정합자3주,미검측출Ⅲ류정합자.Ⅰ류정합자가변구확증편단개우730 ～ 3300 bp,GenBank수거고BLAST분석,검측도8충정합자기인합보,분별위aadB 11주、aac(6’)-Ⅱ7주、aadA5 10주、dfrA17-aadA5 14주、dfrA12-OrfF-aadA2 1주、aacA4-catB8-aadA1 24주、aacC1-OrfA-OrfB-aadA1 3주여catB3-aadB-dhfrV-aacA4-nit-nit2 1주,기중catB3-aadB-dhfrV-aacA4-nit1-nit2시일충신형적내약기인합조합형식;Ⅱ류정합자가변구편단위1600 bp,3주균휴대sat2-aadA1기인합.약민시험표명정합자양성균주대안기당감류화광알류약물내약솔고,여정합자가변구내약기인합적결과상부;양성균주대아미잡성교위민감,내약솔위32.9％(24/73);령외소유균주대다수β-내선알매류약물내약솔≥80％.결론 다중내약혁란음성균Ⅰ류정합자휴대솔교고,차균주내약표형여기정합자가변구내약기인합적류형유상관성.
Objective To explore the correlations of integrons,gene cassettes and drug resistance phenotypes in 90 multi-drug resistant Gram-negative bacteria.Methods Class Ⅰ/Ⅱ/Ⅲ integron and variable region of positive strains of 90 Gram-negative bacteria were amplified by PCR and types of integron variable region gene cassettes analyzed by DNA sequence.And the resistant rates of integron positive and negative strains were tested by drug susceptibility.Results The detection rate of integron was 81.1％ (73/ 90) in 90 Gram-negative bacteria.The integron types were class Ⅰ (n =70),class Ⅱ (n =3) and class Ⅲ (n =0).Based on the BLAST analysis by GenBank database,in the amplified fragments of Class Ⅰ integron positive strains variable region gene ranging from 730 to 3300 bp,8 types of integron structure were identified.And there were aadB (n =11),aac (6')-Ⅱ (n =7),aadA5 (n =10),dfrA17-aadA5 (n =14),dfrA12-OrfF-aadA2 (n =1),aacA4-catB8-aadA1 (n =24),aacCl-OrfA-OrfB-aadA1 (n =3),catB3-aadB-dhfrV-aacA4-nit1-nit2 (n =1),inwhich catB3-aadB-dhfrV-aacA4-nit1-nit2 was a new resistance gene cassette; the variable region fragment of class Ⅱ integron positive strain was 1600 bp,with 3 carrier strains of sat2-aadA1 gene cassette.Susceptibility testing showed that the antimicrobial resistance rate of integron positive strains to aminoglycosides and sulfa were significantly higher than those of integron negative strains and accorded with the results of integration variable region gene cassettes; the positive strains were more sensitive to amikacin with a resistance rate of 32.9％ (24/73) ; and the drug resistance rates of all betalactam strains were ≥ 80％.Conclusions There is a higher carrier rates of class Ⅰ integron in Gramnegative bacteria.And the resistant phenotype is related with the types of resistance gene cassettes of integron variable region.