Electrophoretic Studies of the Mucin Fractions from the Human Gastric Juice. ∗

Summary

1. Electrophoretic analysis was performed on 2 prepared constituents of dissolved mucin from human gastric juice, i.e., glandular mucoprotein from gastric glands and dissolved mucoproteose from surface epithelium as separated by the technic of Glass and Boyd. The patterns obtained from human sources were compared with those obtained on electrophoresis of crystalline porcine pepsin, commercially available hog mucin, and lyophilized and dialyzed canine gastric juice. The runs were done over a wide range of pH and various preparations of these materials were studied with the moving boundary technic. 2. It was found that the electrophoretic pattern of mucoproteose with peaks of slow negative mobility was distinct from that of glandular mucoprotein which displayed a slightly asymmetrical single peak of fast negative mobility. It seems reasonable to conclude that these two substances represent separate constituents of the gastric mucus. Their possible functions will be the subject of later study.