Pea Lipoxidase, Distribution of Enzyme and Substrate in Green Peas

SUMMARY— The activity of the enzyme lipoxidase and the concentrations of free and lipid‐bound fatty acids in different parts of green peas were determined. The extractable enzyme was found mainly in the cotyledon, where its concentration was also highest. The concentration of the enzyme was somewhat higher in the inner than in the outer part of the cotyledon. Both free and bound fatty acids were found in all parts of the pea. The oxidation rate of linoleic acid, catalyzed by lipoxidase, was found independent of oxygen partial pressures above about 20 mm Hg. The respiratory rates of intact and damaged green peas were determined. Based upon these data and on plausible diffusion coefficients, an attempt was made to calculate the oxygen conditions in green peas.