06/20/13 Portland, Ore.
Manganese research in the hot springs of Yellowstone National Park is helping Oregon Health & Science University (OHSU) scientists determine how dynamic and diverse geochemical environments can be used as an early Earth analog.
“Our preliminary enrichments from one manganese (Mn) depositing hot spring suggest the presence of (hyper) thermophilic Mn-oxidizing microorganisms within the microbial communities inhabiting the hot spring,” said Wendy Smythe, a OHSU doctoral student with the Center for Coastal Margin Observation & Prediction at OHSU's Institute of Environmental Health. “However, no microorganism like that has ever been discovered or described.”
A recent National Science Foundation Doctoral Dissertation Improvement Grant was awarded to Wendy Smythe and her advisor, Brad Tebo, head of OHSU’s Division of Environmental & Biomolecular Systems, which will improve the overall quality of her research in geomicrobiology of Mn oxide depositing hot springs in Yellowstone National Park.
“Wendy’s research is significant in identifying biogenic Mn oxides and microfossils associated with modern Mn depositing environments,” Tebo said. “Her results may give scientists a new way to establish criteria for the identification of biosignatures and microfossils present in ancient geological formations.”
Smythe studies the biogeochemistry and microbiology of Mn depositing hot springs to characterize a possibly ancient group of microorganisms and geochemical processes that may have occurred in early Earth environments. Manganese was a critical element in primitive metabolic processes and a key metal as the Earth transitioned from its early anoxic atmosphere to the our present oxic one.
Studies of the geomicrobiology of Mn oxide depositing hot springs will add an important component to the scientific understanding of the overall diversity of these extreme habitats and provide new insights into the role Mn-oxidizing and -reducing microorganisms contribute to Mn oxide mineral formation and preservation.
Smythe plans to explore and characterize possibly the first known Mn-oxidizing single-celled microorganism that thrives in extremely hot environments. She hopes this will expand the scientific knowledge of early life forms and potentially ancient metabolisms.
“The grant will support our efforts to characterize the organisms that live in these hot springs and biogeochemical processes that are causing the oxidation to occur. We will then use that information as a benchmark for what microbial mediated Mn oxide and ancient fossils might look like,” Smythe said.
The specific objectives of this funded research are to:
- identify characteristic biosignatures such as unique oxidation products or biogenic minerals that can be applied to interpret fossilization and the geologic record;
- examine Mn oxide minerals formed around hot springs, and along the outflow channel gradients, from mineral saturated hydrothermal fluids to mineral depleted cooled fluids, to determine the extent of abiotic and biotic mineral formation;
- assess the entire microbial community structure spatially along the Mn-depositing hot spring system to correlate the microbial communities with geochemical parameters and through culturing and characterization of Mn-oxidizing microorganisms;
- determine whether microbial cell surfaces and associated organic polymers serve as templates for formation of specific Mn oxide mineral structures.
Smythe earned a B.S. of biology degree in (2001) and a B.S. of Science with a minor in geology (2004) from Portland State University. She is originally from Hydaburg, Alaska located on Prince of Wales Island and part of a collaborative team implementing a place-based geoscience education program in her Alaska Native community of Haida.
ABOUT OHSU INSTITUTE OF ENVIRONMENTAL HEALTH
OHSU Institute of Environmental Health believes preventative medicine starts with a healthy environment. There is overwhelming evidence that human activities and the global climate are affecting environmental health and sustainability. Increasingly, these consequences are causing serious implications for human health. IEH seeks to develop scientific understanding in environmental and biomolecular systems that elucidates environmental processes and their links to human health.