INSIGHTS INTO THE PANGENOMICS OF DEEP SUBSURFACE THERMOCOCCUS ISOLATES

Hydrothermal vent systems provide rare opportunity to observe the ecology of the deep biosphere, where microorganisms develop interesting adaptations to an extreme, energy-limited environment. The genus Thermococcus is found throughout hydrothermal vents across the world’s oceans. Its members are heterotrophic and reduce S⁰, intimately linking them to carbon and sulfur biogeochemical cycles. Previous characterization of Pacific Ocean Thermococcus isolates through DNA fingerprinting has revealed a unique group isolated from the Gorda Ridge megaplume event of 1996. This subset of isolates is hypothesized to be from the subsurface biosphere, making them putative representatives of the deep subsurface. Advances in genome sequencing technology have made it possible to create pangenomes, or the complete collection of genes for a closely related group of microorganisms. To create a pangenome for these isolates, I will couple second generation Illumina sequencing and Pacific Biosciences SMRT sequencing to construct the collective genomes of the Gorda Ridge isolates. Draft genomes will also be constructed and assembled for many of the remaining isolates. Construction of a pangenome for these Thermococcus isolates will highlight the adaptations that arise to combat the stresses of life in this extreme deep subsurface ecosystem, which will help provide a more complete understanding of Thermococcus’s role in biogeochemical cycling at hydrothermal vent systems throughout the world.