Adegoke Abdulsalam, Kumar Deepak, Bobo Cailyn, Rashid Muhammad Imran, Durrani Aneela Zameer, Sajid Muhammad Sohail, Karim Shahid
Center for Molecular and Cellular Biosciences, School of Biological, Environmental and Earth Sciences, University of Southern Mississippi, Hattiesburg, MS 39406, USA.
Department of Parasitology, Faculty of Veterinary Science, The University of Veterinary and Animal Sciences, Lahore 54000, Pakistan.
Microorganisms. 2020 Aug 25;8(9):1299. doi: 10.3390/microorganisms8091299.
Ticks are blood-feeding arthropods and transmit a variety of medically important viral, bacterial, protozoan pathogens to animals and humans. Ticks also harbor a diverse community of microbes linked to their biological processes, such as hematophagy, and hence affect vector competence. The interactions between bacterial and/or protozoan pathogens and the tick microbiome is a black-box, and therefore we tested the hypothesis that the presence of a protozoan or bacterial pathogen will alter the microbial composition within a tick. Hence, this study was designed to define the microbial composition of two tick species, and . We used a combination of PCR based pathogen ( and species) and symbiont ( species) identification followed by metagenomic sequencing and comparison of the microbial communities in PCR positive and negative ticks. A total of 1786 operational taxonomic units was identified representing 25 phyla, 50 classes, and 342 genera. The phylum Proteobacteria, Firmicutes, Actinobacteriota, and Bacteroidota were the most represented bacteria group. Alpha and beta diversity were not significantly affected in the presence or absence of sp. and as see with ticks. Interestingly, bacterial communities were significantly reduced in sp. infected ticks, while also exhibiting a significant reduction in microbial richness and evenness. Putting these observations together, we referred to the effect the presence of sp. has on a "pathogen-induced dysbiosis". We also identify the presence of , the causative agent of human malaria from the microbiome of both and ticks. These findings support the presence of a "pathogen-induced dysbiosis" within the tick and further validation experiments are required to investigate how they are important in the vector competence of ticks. Understanding the mechanism of "pathogen-induced dysbiosis" on tick microbial composition may aid the discovery of intervention strategies for the control of emerging tick-borne infections.
蜱是吸食血液的节肢动物，可将多种具有重要医学意义的病毒、细菌、原生动物病原体传播给动物和人类。蜱还携带与它们的生物学过程（如吸血）相关的多种微生物群落，从而影响其传播病原体的能力。细菌和/或原生动物病原体与蜱微生物组之间的相互作用仍是一个未知领域，因此我们检验了这样一个假设：原生动物或细菌病原体的存在会改变蜱体内的微生物组成。因此，本研究旨在确定两种蜱的微生物组成。我们结合基于PCR的病原体（和物种）及共生体（物种）鉴定方法，随后进行宏基因组测序，并比较PCR阳性和阴性蜱中的微生物群落。共鉴定出1786个操作分类单元，代表25个门、50个纲和342个属。变形菌门、厚壁菌门（Firmicutes）、放线菌门（Actinobacteriota）和拟杆菌门（Bacteroidota）是最主要的细菌类群。如在蜱中所见，无论有无 种和 种，α和β多样性均未受到显著影响。有趣的是，感染 种的蜱中细菌群落显著减少，同时微生物丰富度和均匀度也显著降低。综合这些观察结果，我们将 种的存在对 的影响称为“病原体诱导的生态失调”。我们还从 和 蜱的微生物组中鉴定出了人类疟疾病原体 。这些发现支持蜱体内存在“病原体诱导的生态失调”，需要进一步的验证实验来研究它们在蜱传播病原体能力中的重要性。了解“病原体诱导的生态失调”对蜱微生物组成的作用机制可能有助于发现控制新出现的蜱传感染的干预策略。
