Intestinal Dipeptidases. IV. Studies on the Release and Subcellular Distribution of Intestinal Dipeptidases of the Mucosa Cells of the Pig

Dipeptidases are released very quickly (10–20 sec) from the mucosa cells of the pig small intestine when mucosa scrapings are placed into aqueous solution. The release is somewhat slower from intact pieces of the intestine but the enzymes are obtained in equal yields. Much higher values of specific activity are obtained this way than when the mucosa cells are homogenized. Distribution of the dipeptidases in the subcellular fractions of the mucosa cells has been determined. The activities are located in the supernatant fraction. No conclusion can be made about the intracellular location of the enzymes because of their rapid release into the solvent. The physiological interpretation of these findings is discussed.