Department of Epidemiology, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou 510515, China.
Int J Food Microbiol. 2011 Jan 5;144(3):337-41. doi: 10.1016/j.ijfoodmicro.2010.10.014. Epub 2010 Nov 12.
Laribacter hongkongensis is a recently discovered bacterium associated with gastroenteritis. In this study, a total of 199 isolates of this species obtained from aquatic products (n=462) in Guangzhou City, China, were examined for their susceptibility to 19 antimicrobial agents and the presence of antimicrobial resistance integrons. The genetic relatedness of the isolates with integrons was also evaluated. A PCR-based method was used to screen integrons and found that 13 (6.5%) of the isolates harbored class 1 integrons. The antimicrobial resistance rates of integron-positive isolates were significantly higher than integron-negative ones for cefepime, ciprofloxacin, gentamicin, tetracycline, trimethoprim-sulfamethoxazole and rifampicin. Genetic sequence analysis revealed that these integrons contained various antimicrobial-resistance genes (dfrA1, dfrA14, dfrA17, dfrA32, aadA1, aadA2, aadA5, cmlA5, arr2, ereA and orfC) organized into different gene cassettes arrangements including a novel array of dfrA14-arr2-cmlA5. Pulsed-field gel electrophoresis (PFGE) yielded 13 different patterns among 13 integron-positive isolates, which could be grouped into four clusters. These indicate the dispersal of multi-resistant integrons among different molecular types. To the best of our knowledge, this is the first report showing distribution and characterization of class 1 integrons among L. hongkongensis isolates.
香港弧菌是一种新近发现的与肠胃炎相关的细菌。在这项研究中，共检测了来自中国广州市水产品（n=462）的 199 株该种细菌，以评估其对 19 种抗菌药物的敏感性以及是否存在抗菌药物耐药性整合子。还评估了携带整合子的分离株的遗传相关性。使用基于 PCR 的方法筛选整合子，发现 13（6.5％）株携带 1 类整合子。整合子阳性分离株的抗菌药物耐药率明显高于整合子阴性分离株，对头孢吡肟、环丙沙星、庆大霉素、四环素、复方新诺明和利福平耐药率更高。遗传序列分析显示，这些整合子包含各种抗菌药物耐药基因（dfrA1、dfrA14、dfrA17、dfrA32、aadA1、aadA2、aadA5、cmlA5、arr2、ereA 和 orfC），排列成不同的基因盒排列，包括 dfrA14-arr2-cmlA5 的新型排列。脉冲场凝胶电泳（PFGE）在 13 株整合子阳性分离株中产生了 13 种不同的图谱，可分为 4 个聚类。这表明多耐药整合子在不同分子类型之间的传播。据我们所知，这是首次报道香港弧菌分离株中 1 类整合子的分布和特征。
