5. Mechanism of the enzymatic synthesis of furan-containing compound

Abstract

Due to the high global demand for petroleum based products and fossil fuels, scientists are actively searching for alternative and bio-renewable energy sources. The US. Department of Energy (DOE) has published a list of the “Top 10 + 4” bio-based chemicals, with furan-containing compounds highlighted for their high potential in the production of biofuels and petroleum based compounds. The enzyme of interest, MfnB, is found most prominently in methanogens and has the ability to takes two molecules of simple compounds glyceraldehyde-3-phosphate to create a furan-containing compound. As one can imagine, industrial applications of MfnB might usher in a new era for the synthesis of furan compounds to be used in the generation of liquid fuel via enzyme-catalyzed reactions. In order to achieve such a goal, we need to first understand how the MfnB enzyme works and the structure of MfnB. In doing so, we can elucidate what makes it unique compared to other enzymes in producing such complex compounds. Through site-directed mutagenesis, kinetic study and structural study, our team seeks to understand MfnB catalytic mechanism. Primers carrying desired mutation have been made, and we are currently in the process of introducing the mutations into the gene. Candidates for mutation were chosen based on structural analysis and a sequence alignment of close relatives of methanogens in which amino acids were conserved. The modifications are introduced in order to determine which amino acids are functional in the mechanistic pathway. Understanding this unique mechanism will add greatly to existing knowledge in the field of biochemistry to determine why this enzyme can carry out five reactions as opposed to the usual two (?).Uncovering the molecular basis of catalytic mystery will serve as the basis for enzyme engineering. The engineered catalytic machinery can then be used for generating building block compounds to meet the needs of industrial biofuel production and the fabrication of other biomaterial products.