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目的对广州市2016年1例霍乱患者进行霍乱弧菌分离鉴定,并与2015年环境及海产品霍乱弧菌分离株进行脉冲场凝胶电泳(PFGE)、耐药性和毒力基因比对分析,分析相关性。方法对1例患者分离株和6株环境海产品分离株,使用XbaI和NotI对标准株和样本株酶切后进行PFGE电泳分析,使用K-β纸片法对11种抗生素进行耐药性实验分析,使用普通PCR方法对ctxA、zot、ace、ompU、tcpA、hlyA、tox R及tcpI共8种毒力相关基因进行分析。结果患者分离株属于II型,环境海产品分离株有两个型别,分别为IA和IB。患者分离株除对磺胺复合物耐药外,对其它药物均敏感。而环境海产品分离株除对磺胺复合物耐药外,还对复方新诺明、四环素和萘啶酸耐药,有更广谱的耐药性。所有样本ctxA均为阴性,hlyA、tcpI和ompU基因全部为阳性。患者基因型为ctxA~-tcpA~-ace~-zot~-,而环境海产品分离株毒力基因多样性比较复杂,和患者分离株相差较大。结论环境海产品分离株携带毒力基因情况复杂,本次患者传染源可能不是来源于监测的环境及海产品。
Objective To isolate and identify Vibrio cholerae in a cholera patient in Guangzhou in 2016 and compare it with that of 2015 by using pulsed-field gel electrophoresis (PFGE) and drug resistance and virulence gene analysis of Vibrio cholera isolates , Analyze the correlation. Methods One patient’s isolate and six isolates of environmental seafood were digested with XbaI and NotI, and then analyzed by PFGE electrophoresis. The antibiotic resistance of 11 antibiotics was tested by K-β method In the analysis, 8 virulence-related genes of ctxA, zot, ace, ompU, tcpA, hlyA, toxR and tcpI were analyzed by ordinary PCR. Results The patient isolates belonged to type II, and there were two types of environmental seafood isolates, IA and IB. In addition to patient isolates resistant to sulfa complex, the other drugs are sensitive. In addition to the environmental seafood isolates resistant to sulfa complex, but also compound cotrimoxazole, tetracycline and nalidixic acid resistance, a broader spectrum of drug resistance. All samples were negative for ctxA and all were positive for hlyA, tcpI and ompU genes. The genotype of the patients was ctxA ~ -tcpA ~ -ace ~ -zot ~ -, while the diversity of virulence genes of the environmental seafood isolates was rather complicated, which was quite different from the isolates of patients. CONCLUSIONS The environmental strains of marine products carry complicated virulence genes, and the source of infection in this case may not originate from the monitored environment and seafood.