Comparative Proteomic Analysis of Naturally Occurring Anaerobic Methane Oxidizing Communities
EMSL Project ID
25672
Abstract
Methane is a potent greenhouse gas whose atmospheric concentration has increased significantly due to anthropogenic activities and fluctuated naturally over glacial and interglacial cycles. While the importance of methane in Earth's climate dynamics has been well established, the global processes regulating its oceanic cycling remain poorly understood. Although there are high rates of methane production in many marine sedimentary environments (including a number which have been targeted as petroleum reserves), net methane sources from the ocean to the atmosphere appear to be small. This is due in large part to a biogeochemical process known as the anaerobic oxidation of methane (AOM). Microbial mediated AOM reduces methane flux from ocean to atmosphere, stimulates subsurface microbial metabolism, and supports vigorous deep-sea chemolithotrophic communities along continental margins and mid-ocean-ridge systems. Despite its widespread significance, the molecular mechanisms underlying AOM are not well understood, in part because the microbial groups known to be involved are difficult to access, exhibit slow in situ growth rates, and remain uncultivated in the laboratory. Previous metagenomic surveys have provided us with a large gene inventory with which to investigate metabolic potentials. We would like to move beyond these inventories to develop a functional understanding of the metabolic networks underlying carbon and energy transformations within AOM sediments. To this end, we are seeking an EMSL users's agreement to conduct shotgun proteomic analysis on diverse marine sedimentary environments, including the Eel River Basin, Santa Barbara Basin and Gulf of Mexico under varying physical and chemical conditions. This work will open a functional genomic window into the metabolic subsystems associated with AOM and provide an invaluable resource for systems level investigations of uncultivated AOM communities under in situ growth conditions. These studies will in turn enhance our mechanistic understanding of an ancient and important biogeochemical phenomenon with real time impact on carbon sequestration and nutrient flow in marine ecosystems around the globe.
Project Details
Project type
Large-Scale EMSL Research
Start Date
2008-01-01
End Date
2009-01-04
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members