September 27, 2018
Dr. Jackie Goordial, Bigelow Laboratory for Ocean Sciences
Microbial activity and ecology through sorted cell -omics of Mid-Atlantic ridge oceanic crust and sediments
Subsurface environments are often characterized by low biomass microbial communities with long generation times, resulting in difficult or impossible to obtain DNA and RNA for downstream genomic analyses of function and activity. We investigated whether flow cytometry could be used to concentrate cells to overcome the limitations due to low biomass in oceanic crust and subsurfacesediment samples from the Mid-Atlantic Ridge. Using single cell flow cytometry sorting coupled with Bioorthogonal noncanonical amino acid tagging (BONCAT), a method to fluorescently tag translationally active microorganisms, we separated active microorganisms from the bulk community of cells to subject only these cells to genomic analyses. In addition to overcoming low biomass, this approach is a step forward to better understanding subsurface microbial systems through molecular techniques, since common methodologies rely on interpreting results from bulk communities of cells regardless of physiological state, including dead, dormant or non-growing cells. I will present genomic data on the activity, identity, and metabolic function of the subsurface sediments and oceanic crust from the Atlantis Massif, and from North Pond rock colonization experiments, both located on the mid-Atlantic ridge.
Dr. Goordial completed a B.Sc. in Cell and Molecular Biology, and a M.Sc in environmental microbiology at the University of Toronto. She completed her Ph.D at McGill University, examining permafrost and cryptoendolithic microbial communities living in polar deserts in the Antarctic and Arctic. Her research employs a combination of genomics and metabolic activity and viability measurements both in situ and in the lab. She currently holds a CDEBI postdoctoral fellowship at Bigelow Laboratory for Ocean Sciences in the laboratory of Dr. Beth Orcutt, where she focuses on the metabolic activity and microbial communities inhabiting marine oceanic crust and sediments.