The ability of the cell to respond to its environment depends on the effective coordination and/or integration of metabolic pathways. For those pathways that involve the biosynthesis of lipophilic signaling molecules, their coordination may be exceptionally challenging in terms of substrate acquisition and specificity, as hydrophobic compounds will partition into the membrane phase, and active sites that recognize bulky hydrophobic substrates might be inherently promiscuous. In order to understand how specificity is achieved in the context of the cell, and how the channeling of intermediates might enhance specificity, we have focused our recent efforts on the structural biology of enzymes involved in the biosynthesis of compounds derived from arachidonic acid released from the membrane by the action of phospholipases. These compounds serve as the precursor for prostaglandins, leukotrienes, thromboxanes, and other biologically active eicosanoids, and the enzymes involved in their biosynthesis represent drug targets, or avenues for the preparation of related compounds for pharmacological uses. In our laboratory we address questions of the regio- and stereo- specificity of these biosynthetic enzymes, as well as how soluble enzymes in this pathway acquire insoluble substrates. Naturally occurring fusion proteins provide us with a system with which to address the structural basis for regio- and stereo- specificity of animal lipoxygenases and their regulation by Ca++, as well as aspects of channeling of intermediates in eicosanoid biosynthetic pathways and protein-protein recognition.
Gilbert, N.C., S.G. Bartlett, M.T. Waight, D.B. Neau, W.E. Boeglin, A.R. Brash, and M.E. Newcomer, The structure of human 5-lipoxygenase. Science, 2011. 331(6014): p. 217-9. [Abstract] [Reprint] [Full Text]
Newcomer, M.E. and N.C. Gilbert, Location, location, location: compartmentalization of early events in leukotriene biosynthesis. J Biol Chem, 2010. 285(33): p. 25109-14.
Neau, D.B., N.C. Gilbert, S.G. Bartlett, W. Boeglin, A.R. Brash, and M.E. Newcomer, The 1.85 A structure of an 8R-lipoxygenase suggests a general model for lipoxygenase product specificity. Biochemistry, 2009. 48(33): p. 7906-15.
Gilbert, N.C., M. Niebuhr, H. Tsuruta, T. Bordelon, O. Ridderbusch, A. Dassey, A.R. Brash, S.G. Bartlett, and M.E. Newcomer, A covalent linker allows for membrane targeting of an oxylipin biosynthetic complex. Biochemistry, 2008. 47(40): p. 10665-76.
Oldham, M.L., A.R. Brash, and M.E. Newcomer, The structure of coral allene oxide synthase reveals a catalase adapted for metabolism of a fatty acid hydroperoxide. Proc Natl Acad Sci U S A, 2005. 102(2): p. 297-302.
Oldham, M.L., A.R. Brash, and M.E. Newcomer, Insights from the X-ray Crystal Structure of Coral 8R-Lipoxygenase:. J Biol Chem, 2005. 280(47): p. 39545-52.