Maryland Pathogen Research Institute, University of Maryland, MD, USA.
FEMS Microbiol Lett. 2010 Jul;308(2):130-7. doi: 10.1111/j.1574-6968.2010.02008.x. Epub 2010 May 6.
This report describes Vibrio seventh pandemic island II (VSP-II) and three novel variants revealed by comparative genomics of 23 Vibrio cholerae strains and their presence among a large and diverse collection of V. cholerae isolates. Three VSP-II variants were reported previously and our results demonstrate the presence of three novel VSP-II in clinical and environmental V. cholerae marked by major deletions and genetic rearrangements. A new VSP-II cluster was found in the seventh pandemic V. cholerae O1 El Tor strain CIRS101, which is dominant (95%) among the recent (2004-2007) seven pandemic V. cholerae O1 El Tor isolates from two endemic sites, but was not found in older strains from the same region. Two other variants were found in V. cholerae TMA21 and RC385, two environmental strains from coastal Brazil and the Chesapeake Bay, respectively, the latter being prevalent among environmental V. cholerae non-O1/non-O139 and Vibrio mimicus. The results of this study indicate that the VSP-II island has undergone significant rearrangement through a complex evolutionary pathway in V. cholerae. Interestingly, one of the new VSP-II revealed the presence of 'old' and 'new' V. cholerae O1 El Tor pandemic clones circulating in some of the areas where cholera is endemic.
本报告描述了弧菌第七次大流行岛 II（VSP-II）和通过比较基因组学发现的三种新型变体，这些变体存在于大量多样的霍乱弧菌分离株中。先前报道了三种 VSP-II 变体，我们的结果表明，三种新型 VSP-II 存在于临床和环境中的霍乱弧菌中，其特征是存在重大缺失和基因重排。在第七次大流行的霍乱弧菌 O1 El Tor 菌株 CIRS101 中发现了一个新的 VSP-II 簇，该菌株在最近（2004-2007 年）两个流行地区的七个大流行的霍乱弧菌 O1 El Tor 分离株中占主导地位（95%），但在同一地区的较老菌株中未发现。另外两种变体存在于霍乱弧菌 TMA21 和 RC385 中，这两种菌株分别是来自巴西沿海和切萨皮克湾的两种环境菌株，后者在非 O1/非 O139 霍乱弧菌和类弧菌中普遍存在。本研究结果表明，VSP-II 岛在霍乱弧菌中经历了通过复杂进化途径的重大重排。有趣的是，新发现的 VSP-II 之一揭示了一些霍乱流行地区存在的“旧”和“新”霍乱弧菌 O1 El Tor 大流行克隆。
