Study of Vegetative Soybean Lipoxygenase

Lipoxygenases are a class of iron-containing enzymes that allow for the hydroperoxidation of polyunsaturated fatty acids. Seed lipoxygenases in soybeans have been purified and well characterized. Plants are also known to have vegetative leaf lipoxygenases. These are not as well characterized because they are not as abundant as their seed counterparts. They are thought to have roles in plant growth and development, in the synthesis of plant regulatory molecules, and in the defense systems of plants against pests and pathogens. The general objective of this study was to analyze soybean leaf lipoxygenases. The specific objectives of this study were to investigate differences in type and amount of leaf lipoxygenase activity as a function of age and strain type and to investigate the effect of extraction conditions on the relative activities of these leaf soybean lipoxygenases. Two sets of soybean seed strains representing control and seed lipoxygenase-free strains are being used. The techniques and procedures of this experiment include isolation of the lipoxygenases from the soybean leaves, separation of the lipoxygenases on an isoelectric focusing gel, specific activity stainingspecific visualization of lipoxygenases and analysis of relative amounts of LOX enzyme using a densitometer. Initial studies indicate differences in LOX patterns in the different strains