Effect of fatty acid chain length and saturation on formation of the acylenzyme complex by the isolated aortic enzyme fraction.

Formation of acylenzyme complexes between the protein fraction isolated from pig thoracic aortas and palmitic, stearic, oleic, linoleic, linolenic and arachidic acid, was studied. The reaction brings about transformations of the periodically variable sinusoidal function of the enzyme absorbancy (energy level) depending on the kind of substrate utilized. Different changes in the enzyme energy level in the elementary process are induced by the saturated and polyunsaturated fatty acids and by oleic acid as demonstrated by the intermediate course of the function for oleylenzyme. The reaction rate constants were calculated and their negative curvilinear dependence upon molecular weight of the substrates has been shown. The differences in the acyl-enzyme reaction course and preferences are discussed with respect to the arterial metabolism and different accumulation of lipids.