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bioRxiv · 10.1101/2021.12.17.473158

An exploratory study on the microbiome of northern and southern populations of Ixodes scapularis ticks predicts changes and unique bacterial interactions

Kumar, D.·Downs, L. P.·Adegoke, A.·Machtinger, E.·Oggenfuss, K.·Ostfeld, R. S.·Embers, M.·Karim, S.
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Abstract

The black-legged tick (Ixodes scapularis) is the primary vector of Borrelia burgdorferi, the causative agent of Lyme disease in North America. However, the prevalence of Lyme borreliosis is clustered around the northern states of the United States of America. This study utilized a metagenomic sequencing approach to compare the microbial communities residing within Ix. scapularis populations from north and southern geographic locations in the USA. Using a SparCC network construction model, potential interactions between members of the microbial communities from Borrelia burgdorferi-infected tissues of unfed and blood-fed ticks were performed. A significant difference in bacterial composition and diversity among northern and southern tick populations was found between northern and southern tick populations. The network analysis predicted a potential antagonistic interaction between endosymbiont Rickettsia buchneri and Borrelia burgdorferi sensu lato. Network analysis, as expected, predicted significant positive and negative microbial interactions in ticks from these geographic regions, with the genus Rickettsia, Francisella, and Borreliella playing an essential role in the identified clusters. Interactions between Rickettsia buchneri and Borrelia burgdorferi sensu lato needs more validation and understanding. Understanding the interplay between the micro-biome and tick-borne pathogens within tick vectors may pave the way for new strategies to prevent tick-borne infections.

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Kumar, D., Downs, L. P., Adegoke, A., Machtinger, E., Oggenfuss, K., Ostfeld, R. S., Embers, M., Karim, S.. 2021-12-19. An exploratory study on the microbiome of northern and southern populations of Ixodes scapularis ticks predicts changes and unique bacterial interactions. https://doi.org/10.1101/2021.12.17.473158

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