Investigation of mechanism and structural dynamics in the human MAPEG enzymatic family.
Our research group is interested in discovering the biochemical mechanism by which inflammatory mediators are produced during the Arachidonic acid cascade. We principally focus on the structure and function of the MAPEG (Membrane-Associated Proteins in Eicosanoid and Glutathione metabolism) family of enzymes, and seek to complement cutting edge experimental studies of their structural dynamics with computational analysis using the resources provided by NSC. A particular member of this family, microsomal prostaglandin E synthase 1 (mPGES-1), catalyses the synthesis of PGE2 from PGH2 (produced by cyclooxygenases from arachidonic acid). PGE2 is a powerful mediator of pain and inflammation, and mPGES-1 is the principal source of inducible PGE2 under pro-inflammatory conditions. Since it is also the terminal enzyme is this biosynthetic pathway, it has emerged as an interesting drug target for the development of non-steroidal anti-inflammatory drugs. Recently, we have probed the enzymatic mechanism using assays involving active site mutants in combination with experimental structural dynamics (1). This work was performed in part, using resources allocated on by SNIC. In contrast to a serine active site residue suggested by the crystal structure, our analysis implicates a dynamic arginine-aspartate salt bridge as essential for catalysis, and that the presence of membrane fine tunes the catalytic machinery. We would like to elaborate on these results further using SNIC resources, comparing and cross validating room temperature X-ray diffraction data with molecular dynamics simulations and the discovery of novel pharmaceuticals with docking software. 1. Brock, J. S., Hamberg, M., Balagunaseelan, N., Goodman, M., Morgenstern, R., Strandback, E., et al. (2016). A dynamic Asp-Arg interaction is essential for catalysis in microsomal prostaglandin E2 synthase. Proceedings of the National Academy of Sciences of the United States of America, 113(4), 201522891–977. http://doi.org/10.1073/pnas.1522891113