摘要
旨在调查鸭致病性大肠杆菌氨基糖苷修饰酶耐药基因(AMEs基因)的携带情况,探讨耐药基因与氨基糖苷类抗生素耐药表型的相关性。对98株鸭致病性大肠杆菌采用了K-B法,选用氨基糖苷类抗生素链霉素、新霉素、庆大霉素、阿米卡星、大观霉素和卡那霉素进行药敏试验,用建立的检测氨基糖苷类AMEs主要基因的四重PCR方法对上述菌株进行分子检测,并随机选取耐药基因ant(3″)-Ⅰa、aac(3)-Ⅱa和aph(3′)-Ⅱa各3个阳性扩增进行克隆测序,对药敏试验结果和基因检测结果进行比较分析。结果表明,98株鸭致病性大肠杆菌有67株对上述氨基糖苷类药物中的一种或多种耐药,耐药率为68.4%(67/98);有49株扩增出AMEs基因,AMEs基因的检出率为50%(49/98),其中ant(3″)-Ⅰa的检出率为30.6%(30/98),aac(3)-Ⅱa为13.3%(13/98),aph(3′)-Ⅱa为3.1%(3/98),ant(3″)-Ⅰa+aac(3)-Ⅱa为2.0%(2/98)、aac(3)-Ⅱa+aph(3′)-Ⅱa为1.0%(1/98),未检出aac(6′)-Ⅰb基因;序列分析结果表明,扩增产物与GenBank中的相应序列有很高的同源性(>99%);AMEs耐药基因与耐药表型的符合率为73.1%(49/67),符合率从高到低依次为大观霉素60%(3/5)、庆大霉素55%(11/20)、链霉素33.3%(22/66)、卡那霉素19%(4/21)、新霉素12.5%(1/8)、阿米卡星0%(0/3)。另外有4株细菌检测到相关耐药基因但耐药表型为敏感,而有22株耐药表型为耐药却未检测到相关耐药基因。鸭致病性大肠杆菌氨基糖苷类耐药基因以ant(3″)-Ⅰa和aac(3)-Ⅱa两种为主,耐药性与相关耐药基因的检出率基本呈正相关。
The objective of this paper is to investigate aminoglycoside resistance genes in E.coli from ducks and to study the correlation between the phenotypes and the genotypes of resistance.By using the K-B method and choosing aminoglycoside antibiotics including streptomycin（STR）,neomycin（NEO）,gentamycin（GEN）,kanamycin（KAN）,amikacin（AMK） and spectinomycin（SPT）,the drug sensitivity tests were conducted for 98 strains of pathogenic E.coli from ducks.All strains of E.coli were detected by multiplex PCR method based on the main genes of AMEs to aminoglycoside,the resistance genes including ant（3″）-Ⅰa,aac（3）-Ⅱa and aph（3＇）-Ⅱa randomly selected from 3 E.coli strains with positive amplification were cloned and sequenced,then the results obtained from drug sensitivity tests were compared with that of PCR detection.The results showed that 67 strains out of 98 strains are resistant to one or several antibiotics with the resistance rate of 68.4%（67/98）,and AMEs genes were amplified in 49 strain of the bacteria with the positive rate of 50%（49/98）,in which the detection rates of ant（3″）-Ⅰa,aac（3）-Ⅱa,aph（3＇）-Ⅱa,ant（3″）-Ⅰa＋aac（3）-Ⅱa and aac（3）-Ⅱa＋aph（3＇）-Ⅱa were 30.6%（30/98）,13.3%（13/98）,3.1%（3/98）,2.0%（2/98） and 1.0%（1/98） respectively,and aac（6＇）-Ⅰb wasn＇t be discovered.The sequences analysis indicates that the amplified products shared high homology（over 99%） with the corresponding sequences in GenBank.The results of comparison show that the correlation rate between phenotype and genotype of resistance gene AMEs is 67%（45/67）,in which the correlation rates of SPT,GEN,STR,KAN,NEO and AMK were 60%（3/5）,55%（11/20）,33.3%（22/66）,19%（4/21）,12.5%（1/8） and 0%（0/3）,respectively.In addition,4 strains carrying resistance genes showed the sensitive phenotype,while 22 strains with resistance phenotype didn＇t carrying the relevant genes.The main resistance genes of pathogenic E.coli from ducks to aminoglycoside are ant（3″）-Ⅰa and aac（3）-Ⅱa,and the drug resistance is positively correlative to the detection rate of relevant resistance genes.
出处
《畜牧兽医学报》
CAS
CSCD
北大核心
2010年第12期1568-1575,共8页
ACTA VETERINARIA ET ZOOTECHNICA SINICA
基金
国家科技支撑计划(2006BAD06A11)
国家科技支撑计划(2009BADB4B01)
