摘要
目的了解天津地区志贺菌1类、2类整合子及插入序列共同区(ISCR1)携带情况及其与耐药性的关系。方法 K-B纸片扩散法测定临床分离的159株志贺菌的药敏情况。以煮沸法制备细菌总DNA作为PCR扩增模板。采用PCR方法扩增1类、2类整合子及ISCR1并测序分析。PCR产物直接测序,结果经BLAST程序与Gen-Bank数据库标准株比对分析。结果 159株志贺菌中,53株福氏志贺菌对四环素的耐药率最高88.68%,其次是链霉素81.13%、氯霉素及SMZco均为56.60%,多重耐药率77.36%;106株宋氏志贺菌对氨苄西林的耐药率最高97.17%,其次是SMZco95.28%、四环素83.96%、庆大霉素76.42%,多重耐药率98.11%。1类整合子阳性118株,其中典型1类整合子23株,共有5种基因盒,分别为aad A2、aad A1、dfrⅠ、blaoxa-10及blaoxa-1;非典型1类整合子95株,基因包括int I1、aad A、blaoxa-1和IS1等;2类整合子阳性89株,其基因盒有dfr A1、satl及aad A1;1类、2类整合子同时阳性的菌株70株。未发现ISCR1阳性菌株。整合子阳性菌株中多重耐药率高于整合子阴性菌株(90.65%vs 50%,P<0.05)。结论 1、2类整合子广泛存在于志贺菌中且与志贺菌的多重耐药相关。
Objective To explore carrying rates of class 1, class 2 integrons as well as ISCR1 in Shigella isolates and their connection with drug resistance. Methods Antibiotic sensitivities were detected by K-B disk diffusion in 159 clinical isolates. Total bacteria DNA was prepared through boiling the isolates and the DNA was then used as template for PCR am？plification. PCR, ZSCR1 and sequencing analyse of integrons were applied to all of them. Results were compared by Blast and GenBank. Results Antibiotic sensitivity results showed that in the S. flexneri strains the incidence of resistance to tet？racycline and streptomycin were 88.68%and 81.13%in the S. flexneri strains while the incidence of resistant to chloram？phenicol and trimethoprim-sulfamethoxazol were both 56.60%, and the incidence of multidrug drug resistance was 77.36%. In the sonnei strains, the incidence of resistance to ampicillin, trimethoprim-sulfamethoxazo were 97.17% and 95.28%, 83.96%and 76.42%respectively, and the incidence of multidrug resistance was 98.11%. Among all isolates, 118 were class 1 integron positive , 70 were class 2 integron positive and 89 were double positives. For those 118 isolates that are positive of class 1 integron, 23 were typical while 95 weres atypical. The gene cassettes of typical class 1 integrons contains aadA2, aa？dA1, dfrⅠ, blaoxa-10 and blaoxa-1. IntI1, aadA, blaoxa-1 and IS1 were included in the gene cassetes of the atypical class 1 integrons. Class 2 integrons positive isolates carried gene cassttes which include dfrA1, satl and aadA1. No ISCR1 was found in any isolate. Integron carriage strains were closely associated with higher rate of multiple antibiobic resistance com？pared with the organisms without integrons （90.65%,50%, P＆lt;0.05）. Conlusion Class 1 and class 2 integrons were widely existence in Shigella isolates and were related to the multidrug resistance.
出处
《天津医药》
CAS
2015年第4期400-403,共4页
Tianjin Medical Journal
关键词
志贺菌属
整合子类
耐药性
微生物
序列共同区
shigella
integrons
drug resistance,microbiol
sequence common region
