USAP-DC

Despite recent advances, we still know little about how life and its traces persist in extremely harsh conditions. What survival strategies do cells employ when pushed to their limit? Using a new technique, this project will investigate whether Antarctic paleolakes harbor "microbial seed banks," or caches of viable microbes adapted to past paleoenvironments that could help transform our understanding of how cells survive over ancient timescales. Findings from this investigation could also illuminate novel DNA repair pathways with possible biomedical and biotechnology applications and help to refine life detection strategies for Mars. The project will bring Antarctic research to Georgetown University''s campus for the first time, providing training opportunities in cutting edge analytical techniques for multiple students and a postdoctoral fellow. The field site will be the McMurdo Dry Valleys, which provide an unrivaled opportunity to investigate fundamental questions about the persistence of microbial life. Multiple lines of evidence, from interbedded and overlying ashfall deposits to parameterized models, suggest that the large-scale landforms there have remained essentially fixed as far back as the middle of the Miocene Epoch (i.e., ~8 million years ago). This geologic stability, coupled with geographic isolation and a steady polar climate, mean that biological activity has probably undergone few qualitative changes over the last one to two million years. The team will sample paleolake facies using sterile techniques from multiple Dry Valleys sites and extract DNA from entombed organic material. Genetic material will then be sequenced using Pacific Biosciences'' Single Molecule, Real-Time DNA sequencing technology, which sequences native DNA as opposed to amplified DNA, thereby eliminating PCR primer bias, and enables read lengths that have never before been possible. The data will be analyzed with a range of bioinformatic techniques, with results that stand to impact our understanding of cell biology, Antarctic paleobiology, microbiology and biogeography, biotechnology, and planetary science.

Person	Role
Johnson, Sarah	Investigator and contact
Zaikova, Elena	Researcher
Goerlitz, David	Researcher
Tighe, Scott	Researcher
Bai, Yu	Researcher
Greenfield, Samuel	Researcher
Hall, Brenda	Researcher
Weng, Margaret	Researcher
Bevilacqua , Julie	Researcher
Samuels-Fair, Maya	Researcher
Wagner, Nicole	Researcher
Von Turkovich, Michelle	Researcher
Taatjes, Douglas	Researcher
Dragon, Julie	Researcher

Antarctic Earth Sciences	Award # 1620976
Antarctic Organisms and Ecosystems	Award # 1620976

USAP-1620976_1

Deployment	Type
Antarctica	general deployment

EAGER_Data_Management_Plan.docx

Repository	Title (link)	Format(s)	Status
NCBI GenBank	GenBank Sequence Read Archive with accession numbers SRR8217969 - SRR8217976 and project accession PRJNA506221	ASCII	exists

1. Zaikova, E, DS Goerlitz, SW Tighe, NY Wagner, Y Bai, BL Hall, JG Bevilacqua, MM Weng, MD Samuels-Fair, and SS Johnson, 2019. Antarctic Relic Microbial Mat Community Revealed by Metagenomics and Metatranscriptomics, Frontiers in Ecology and Evolution, doi.org/10.3389/fevo.2019.00001. (doi:10.3389/fevo.2019.00001)
2. Greenfield, SR, SW Tighe, Y Bai, DS Goerlitz, M Von Turkovich, DJ Taatjes, JA Dragon, and SS Johnson, 2020. Life and its Traces in Antarctica’s McMurdo Dry Valley Paleolakes: A Survey of Preservation, Micron, 131. doi.org/10.1016/j.micron.2019.102818. (doi:10.1016/j.micron.2019.102818)
3. Johnson, SS, E Zaikova, D Goerlitz, Y Bai, and S Tighe, 2017. Real Time DNA Sequencing in the Antarctic Dry Valleys using the Oxford Nanopore Sequencer. Journal of Biomolecular Techniques, 28(1), 2-7, doi: 10.7171/jbt.17-2801-009. (doi:10.7171/jbt.17-2801-009)