Vibrio parahaemolyticus is a marine bacterium and causes opportunistic gastroenteritis in humans. Clinical strains of V. parahaemolyticus contain haemolysin and type III secretion systems (T3SS) that define their pathotype. A growing number of strains isolated recently from the environment have acquired these virulence genes constituting a pool of potential pathogens. This study used comparative genomics to identify genetic factors that delineate environmental and clinical V. parahaemolyticus population and understand the similarities and differences between the T3SS2 phylotypes. The comparative analysis revealed the presence of a cluster of genes belonging to bacterial cellulose synthesis (bcs) in isolates of environmental origin. This cluster, previously unreported in V. parahaemolyticus, exhibit significant similarity to that of Aliivibrio fischeri, and might dictate a potentially new mechanism of its environmental adaptation and persistence. The study also identified many genes predicted in silico to be T3SS effectors that are unique to T3SS2β of tdh⁻trh⁺ and tdh⁺trh⁺ pathotype and having no identifiable homologue in tdh⁺trh⁻ T3SS2α. Overall, these findings highlight the importance of understanding the genes and strategies V. parahaemolyticus utilize for the myriad interactions with its hosts, either marine invertebrates or humans.

中文翻译：

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副溶血性弧菌环境和临床分离株之间的基因组属性不同，包括致病型

副溶血性弧菌是一种海洋细菌，可引起人类机会性胃肠炎。副溶血性弧菌的临床菌株含有溶血素和 III 型分泌系统 (T3SS)，这些系统定义了它们的致病型。最近从环境中分离出的越来越多的菌株已经获得了构成潜在病原体库的这些毒力基因。本研究使用比较基因组学来确定描述环境和临床副溶血性弧菌种群的遗传因素，并了解 T3SS2 系统型之间的异同。比较分析表明存在一组属于细菌纤维素合成的基因（bcs) 在环境来源的分离物中。这个集群，以前在副溶血性弧菌中未报道，与Aliivibrio fischeri具有显着的相似性，并且可能决定了其环境适应和持久性的潜在新机制。该研究还确定了许多在计算机上预测为 T3SS 效应子的基因，这些基因是tdh ^- trh ⁺和tdh ⁺ trh ⁺致病型的 T3SS2β 所特有的，并且在tdh ⁺ trh ^- T3SS2α中没有可识别的同源物。总体而言，这些发现强调了了解基因和策略的重要性V. parahaemolyticus利用与其宿主（海洋无脊椎动物或人类）的无数相互作用。