Lockwood Svetlana, Brayton Kelly A, Broschat Shira L
School of Electrical Engineering and Computer Science, Washington State University, P.O. Box 642752, Pullman, USA.
Department of Veterinary Microbiology and Pathology, Washington State University, P.O. Box 647040, Pullman, 99164-7040, USA.
BMC Genomics. 2016 Jul 2;17:481. doi: 10.1186/s12864-016-2744-9.
Multiple important human and livestock pathogens employ ticks as their primary host vectors. It is not currently known whether this means of infecting a host arose once or many times during evolution.
In order to address this question, we conducted a comparative genomics analysis on a set of bacterial pathogens from seven genera - Borrelia, Rickettsia, Anaplasma, Ehrlichia, Francisella, Coxiella, and Bartonella, including species from three different host vectors - ticks, lice, and fleas. The final set of 102 genomes used in the study encoded a total of 120,046 protein sequences. We found that no genes or metabolic pathways were present in all tick-borne bacteria. However, we found some genes and pathways were present in subsets of tick-transmitted organisms while absent from bacteria transmitted by lice or fleas.
Our analysis suggests that the ability of pathogens to be transmitted by ticks arose multiple times over the course of evolution. To our knowledge, this is the most comprehensive study of tick transmissibility to date.
多种重要的人类和家畜病原体以蜱作为其主要宿主传播媒介。目前尚不清楚这种感染宿主的方式在进化过程中是出现过一次还是多次。
为了解决这个问题，我们对来自七个属的一组细菌病原体进行了比较基因组学分析，这七个属包括疏螺旋体属、立克次体属、无形体属、埃立克体属、弗朗西斯菌属、柯克斯体属和巴尔通体属，其中的物种来自三种不同的宿主传播媒介——蜱、虱子和跳蚤。该研究中使用的最终102个基因组集总共编码了120,046个蛋白质序列。我们发现并非所有蜱传细菌中都存在某些基因或代谢途径。然而，我们发现一些基因和途径存在于蜱传播的生物体子集中，而在虱子或跳蚤传播的细菌中不存在。
我们的分析表明，病原体通过蜱传播的能力在进化过程中出现过多次。据我们所知，这是迄今为止关于蜱传播性的最全面研究。
