Department of Microbiology, Tehran University of Medical Sciences, Tehran, Iran.
Department of Bacteriology, Tarbiat Modares University, Tehran, Iran.
J Med Microbiol. 2011 Dec;60(Pt 12):1742-1749. doi: 10.1099/jmm.0.031732-0. Epub 2011 Aug 18.
In this study 86 isolates of Vibrio cholerae were analysed for their adhesive properties and the presence of pathogenicity island genes. With the exception of three isolates, all of the other clinical isolates (92.5%) contained an intact TCP (toxin-co-regulated pilus) gene cluster. In contrast, 95% of all environmental non-O1-non-O139 isolates were negative for the TCP gene cluster. The majority of clinical isolates (82.5%) possessed the complete vibrio pathogenicity island (VPI) gene cluster and had a similar RFLP pattern, while only a single environmental strain possessed an almost complete VPI cluster (lacking 0.4 kb in the tcpA and toxT region). The result showed that the isolates with tcpA(+)/toxT(+) had a strong attachment for HT-29 and Vero cells, whereas isolates with tcpA(+)/toxT(-) or tcpA(-)/toxT(-) genomic characteristics showed no autoagglutination and weak attachment for the cell lines. Two environmental strains (tcpA(-)/toxT(-)) showed strong adhesive properties to the cell lines, indicating that non-fimbrial adhesive factors are involved in the environmental V. cholerae strains in the absence of TCP.
在这项研究中，分析了 86 株霍乱弧菌的粘附特性和致病性岛基因的存在。除了 3 株分离株外，其他所有临床分离株（92.5%）都含有完整的 TCP（毒素调节菌毛）基因簇。相比之下，所有环境中非-O1-非-O139 分离株中，95%的分离株 TCP 基因簇呈阴性。大多数临床分离株（82.5%）都具有完整的霍乱弧菌致病性岛（VPI）基因簇，且具有相似的 RFLP 模式，而仅有一株环境分离株具有几乎完整的 VPI 簇（在 tcpA 和 toxT 区域缺失 0.4kb）。结果表明，tcpA(+) / toxT(+)的分离株对 HT-29 和 Vero 细胞具有强烈的粘附性，而 tcpA(+) / toxT(-)或 tcpA(-)/toxT(-)基因组特征的分离株则不发生自凝集，对细胞系的粘附性较弱。两株环境分离株（tcpA(-)/toxT(-)）对细胞系表现出强烈的粘附性，表明在缺乏 TCP 的情况下，非菌毛粘附因子参与了环境中霍乱弧菌的粘附。
