With this award, the Chemistry of Life Processes Program in the Division of Chemistry is funding Professor Mishtu Dey of the University of Iowa to study the structure and mechanism of the the enzyme methyl coenzyme M reductase (MCR). Biological methane is produced by a process called methanogenesis through the action of a group of microbes called methanogens. The methanogens use simple one- and two-carbon compounds as substrates to form methane utilizing one of Nature's most fascinating nickel enzymes, methyl coenzyme M reductase. Approximately one billion tons of methane is generated every year by methanogenesis. In view of its relative abundance and clean burning properties, methane continues to be an attractive fuel. On the other hand, methane is also a potent greenhouse gas. This project is focused on elucidating specific aspects of the mechanism of function of MCR. A greater understanding of MCR mechanism and the process of methanogenesis may enable design of enzymes for reducing agricultural methane emissions and provide a basis for improving bioreactor technology to produce, capture, and store methane as a source of sustainable energy. The research plan is integrated into an interactive science project to engage middle school students in the art of crystallography.
The objective of this project is to investigate the mechanism of methane formation by MCR and biosynthesis of unusual post-translational modifications (PTMs) present in this globally important metalloenzyme responsible for biological methane production. Here, structural and mechanistic enzymology approaches are used to investigate enzyme-catalyzed C-heteroatom bond activation and biological methylation reactions. The proposed studies may provide important insights into the mechanism of biological methane formation and may illuminate Nature's strategies to carry out unusual PTMs. The knowledge gained from the proposed research offers important insights into how energy-rich molecules, such as methane, are synthesized within the hydrophobic reaction chamber of a buried metalloenzyme active site. The comprehensive structure-function study has applications in bioengineering and bioenergy/biofuel industries. The proposed project involves training students at various levels of education.