The major focus of Dr. Brash’s research is the biosynthesis of oxygenated metabolites of essential fatty acids (polyunsaturated fatty acids). Current projects include analysis of different lipoxygenase enzymes and how they control the stereochemistry of their individual fatty acid hydroperoxide products. A related area of interest is heme-containing enzymes that have evolved to metabolize fatty acid peroxides. These include certain cytochrome P450s and also relatives of catalase (the defense enzyme that normally metabolizes hydrogen peroxide). We are also studying the involvement of lipoxygenase enzymes in epithelial cell function: two of the six human lipoxygenase genes exhibit neonatal lethality in the mouse knockout and we are dissecting the biochemical mechanisms underlying their in vivo functioning.