The majority of all life forms obtain energy for growth by transferring electrons from one molecule (the growth substrate) to another (electron acceptor). The electrons are carried through the membrane by proteins and small organic compounds accompanied by the pumping of protons or sodium ions from inside to outside the membrane. The resulting ion gradient drives the phosphorylation of adenosine diphosphate (ADP) producing adenosine triphosphate (ATP). The dephosphorylation of ATP back to ADP provides the energy for reactions required for biosynthesis of cellular components leading to growth. This process of electron transport phosphorylation of ADP is also how methane-producing anaerobic (living without oxygen) microorganisms obtain energy for growth. However, little is known of the membrane components that transfer the electrons. An understanding of this important process is necessary to develop processes for conversion of plant material to clean burning methane as an alternative to fossil fuels. Recently, a complex of several proteins (Rnf) first discovered in microorganisms from the Bacteria domain of life was shown to be present in Methanosarcina acetivorans, a methane producing species from the Archaea domain of life. Only recently discovered, investigations of Rnf complexes are in their infancy and no Rnf complexes from the Archaea domain of life have been investigated. The project involves an investigation of the Rnf complex from M. acetivorans. The results are expected to initiate the transformation from a cursory to a comprehensive understanding of the Rnf family that will also advance a general understanding of diverse electron transport process in organisms spanning all domains of life. Broader impacts. The project provides an exceptionally fertile ground for training students that will prepare them for a productive career and ensure a sound scientific infrastructure. Minority and disadvantaged students will be actively recruited with the goal of increasing vitality in the scientific enterprise through diversity. The project will support outreach activities with pre college educators with the goal of developing an interest in science among women, minorities and disadvantaged students. Finally, undergraduates will be recruited for a research experience that will prepare them for graduate school.
