What Can Slimy Rocks in the Deep Sea Tell Us about Microbial Survival Strategies at High Temperatures? Matt Schrenk

Thursday, 25 Feb 2010 at 7:00 pm – South Ballroom, Memorial Union

Matt Schrenk is an assistant professor of microbiology at East Carolina University in Greenville, North Carolina. Most of his research has focused upon the growth of microorganisms on mineral surfaces, in communities known as biofilms. He is particularly interested in the ecological and evolutionary roles of biofilms in some of the highest temperature ecosystems on Earth - at the deep-sea hydrothermal vents. Schrenk participated in the recovery of the largest sulfide chimney structures to date from the Juan de Fuca Ridge in 1998 and later had the opportunity to conduct the first microbiological analyses of the newly discovered carbonate towers from the Lost City Field in 2001. He received his B.Sc. in Geology and Geophysics from the University of Wisconsin-Madison and his Ph.D. in Oceanography with a certificate in astrobiology from the University of Washington.

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Hydrothermal systems, like the 'black smoker' chimneys at mid–ocean ridges, are some of the most dynamic and extreme environments colonized by life and may have been inhabited since early in Earth's history. Biofilms, or 'microbial mats', attached to rocks were amongst the first forms of microbial life discovered at hydrothermal vents thirty years ago and have since been found in terrestrial hot springs and shallow submarine hydrothermal habitats. Studies of high temperature microbial ecosystems have been a rich source of genetic and functional diversity and novel enzymes for biotechnology. While biofilms have been extensively characterized in medical and industrial settings, their role(s) in natural ecosystems are only now beginning to be elucidated. Some of the roles that biofilms may play include improving microbial resilience to environmental stresses and thereby expanding the range of potentially habitable conditions. Biofilms also serve to 'tether' microorganisms in the otherwise dynamic and rapidly–changing habitats found at deep sea vents. Furthermore, biofilms may bind nutrients and facilitate cooperative relationships between organisms, or serve as food for higher trophic levels. The growth of microbial communities as biofilms has a number of properties and a level of complexity that would be hard to recognize if studied individually.

Comparative studies of biofilm structure and composition in hydrothermal environments are beginning to make headway into understanding high temperature microbial 'slimes'. The interactions between biofilms and mineral surfaces at hydrothermal vents play a prominent role in many scenarios speculated for the origins of life on Earth, and surface–associated biofilms may contain a record of these molecular interactions. Insights from biofilm studies also provide us with a better extent of the depths and potential extent of the deep subsurface biosphere. Finally, findings from modern–day hydrothermal systems on Earth may help to focus life detection efforts on volcanically active planets elsewhere in the universe.

Cosponsored By:

• Ecology, Evolution, and Organismal Biology
• Environmental Science Program
• Geology & Atmospheric Sciences
• Microbiology Program
• NSF Ridge 2000 Program
• Committee on Lectures (funded by Student Government)