The acid polysaccharides of hog gastric mucosa

Abstract

The enzyme isolated from ox pancreas is similar in its specificity to the enzyme isolated by Fairbairn (1948) from PeniciUium notatum. In both cases no activity was discovered against lecithin. The pH optima are different, being 4-0 with the Penicillium enzyme and 3-5 for the enzyme found inA8pergillu8 oryzae by Contardi & Ercoli (1933). It was not esta- blished in this work whether the enzyme attacks lysocephalin, since no purified substrate was avail- able. Our substrate of lysolecithin contained small amounts of lysocephalin, not in quantities large enough, however, to disturb significantly the equi- valence between the ester splitting and the glycero- phosphoryleholine formation. In the case of the Penicillium enzyme, Fairbairn (1948) showed that some ethanolamine could be demonstrated in the glycerophosphorylcholine fraction liberated by the enzyme. Thus, it is very likely that the enzymes discussed are lysophospholipases, rather than specific lysolecithinases.