Abstract:
Melioidosis is an often-fatal neglected tropical disease caused by an environmental bacterium Burkholderia pseudomallei. However, our understanding of the disease-causing bacterial lineages, their dissemination, and adaptive mechanisms remains limited. To address this, we conduct a comprehensive genomic analysis of 1,391 B. pseudomallei isolates collected from nine hospitals in northeast Thailand between 2015 and 2018, and contemporaneous isolates from neighbouring countries, representing the most densely sampled collection to date. Our study identifies three dominant lineages, each with unique gene sets potentially enhancing bacterial fitness in the environment. We find that recombination drives lineage-specific gene flow. Transcriptome analyses of representative clinical isolates from each dominant lineage reveal increased expression of lineage-specific genes under environmental conditions in two out of three lineages. This underscores the potential importance of environmental persistence for these dominant lineages. The study also highlights the influence of environmental factors such as terrain slope, altitude, and river direction on the geographical dispersal of B. pseudomallei. Collectively, our findings suggest that environmental persistence may play a role in facilitating the spread of B. pseudomallei, and as a prerequisite for exposure and infection, thereby providing useful insights for informing melioidosis prevention and control strategies.
摘要:
类lioidosis是一种通常致命的被忽视的热带病,由环境细菌Burkholderiapseudomallei引起。然而,我们对致病细菌谱系的理解,他们的传播,适应性机制仍然有限。为了解决这个问题,我们对2015年至2018年从泰国东北部9家医院收集的1391株假单胞菌分离株以及来自邻国的同期分离株进行了全面的基因组分析,代表迄今为止采样最密集的集合。我们的研究确定了三个优势谱系,每个都具有独特的基因集,可能增强环境中的细菌适应性。我们发现重组驱动谱系特异性基因流。来自每个显性谱系的代表性临床分离株的转录组分析揭示了在环境条件下三个谱系中的两个谱系中谱系特异性基因的表达增加。这强调了环境持久性对这些优势谱系的潜在重要性。该研究还强调了地形坡度等环境因素的影响,高度,和河流方向对B.pseudomallei地理分布的影响。总的来说,我们的研究结果表明,环境持久性可能在促进假单胞菌的传播中起作用,作为暴露和感染的先决条件,从而为预防和控制策略提供有用的见解。