2014 Annual Science Report
VPL at University of Washington Reporting | SEP 2013 – DEC 2014
Biogenic Gases From Anoxygenic Photosynthesis in Microbial Mats
This lab and field project aims to measure biogenic gas fluxes in engineered and natural microbial mats composed of anoxygenic phototrophs and anaerobic chemotrophs, such as may have existed on the early Earth prior to the advent of oxygenic photosynthesis. The goal is to characterize the biogeochemical cycling of S, H, and C in an effort to constrain the sources and sinks of gaseous biosignatures that may be relevant to the detection of life in anoxic biospheres on habitable exoplanets.
Field measurements were initially scheduled for summer 2014 to measure biogenic gases produced by anoxygenic mats dominated by the green non-sulfur filamentous anoxygenic phototroph Chloroflexus. However, the Yellowstone Research Permit Office notified us in June 2014 that we would not be allowed to sample the green Chloroflexus mats at New Pit Spring at Mammoth due to safety concerns. As a result, we contacted senior researcher Richard Castenholz from the University of Oregon and he showed us safer green Chloroflexus mats to sample during a field trip in August 2014 (Fig. 1). A permit will be obtained for these new sites and the biogenic gas measurements will be performed during summer 2015. We also will measure biogenic gases in a rooftop lab greenhouse at NASA Ames Research Center in which microbial mats from Guerrero Negro, Mexico, have been maintained long-term. This greenhouse is in the process of being relocated.
PROJECT MEMBERS:Niki Parenteau
RELATED OBJECTIVES:Objective 4.1
Earth's early biosphere.
Co-evolution of microbial communities
Biochemical adaptation to extreme environments
Effects of environmental changes on microbial ecosystems
Adaptation and evolution of life beyond Earth
Biosignatures to be sought in nearby planetary systems