Dissolved mucoproteose

Thus, along with the secretion of surface epithelium mucus and its mechanical shedding, there must be a constant digestion of mucus by a mucolytic enzyme present in the mucus itself (G26, G33, G34). However, the mechanism of removal of mucus from gastric mucosa with formation of its degradation product, detectable in the gastric juice as "dissolved mucoproteose (G27) needs clarification. 

As stated in 1953 (Gll) Dissolved mucoproteose is not a chemical entity, but a complex of intermediate products of digestion of gastric mucus. For this reason, the peptide moiety of this fraction may show transitions between the first and further split products of enzymatic degradation of proteins (proteans, primary and secondary proteoses, and even peptones). This is why one part of the mucoproteose fractions is dialyzable, and disappears from the electrophoretic partition of the dialyzed gastric juice. ... 

G36. Glass, G. B. J., Boyd, L. J., Heisler, A., and Drekter, I. J., Studies on dissolved mucin of the gastric juice. III. Heterogeneity of the gastric dissolved mucin and its differentiation and separation into two main fractions Dissolved mucoproteose and dissolved mucoprotein. Bull. N.Y. Med. Coll. Flower Fifth Ave. Hosp. 2, 8-48 (1948). 

Hexosamine to Tyrosine Ratio in Mucoprotein H (= Mucoproteose) and Mucoprotein V (= Glandular Mucoprotein) Fractions of Dissolved Gastric Mucin Collected Under Similar Conditions from Heidenhain Pouches of 4 Docs... 

As we know at present, the mucoproteose fraction includes the following materials (1) most of the gastric fucomucins, as well as some of the blood group substances, i.e., most of the neutral polysaccharides of the dissolved mucin fraction linked to their peptide moiety, (2) y-globulin and probably also P-globulin, which pass into the gastric juice from the serum (G16, G42, Hll, H20, H55) and probably account for the presence of mannose in this fraction (Gll), (3) some of the pep-tidic degradation products of serum albumin and visible mucus, which are partly dialyzable (G16, K2), (4) native intrinsic factor, the related primary vitamin Bi2 binder, and tertiary vitamin Bia binder related to the neutral mucosubstances (G14, Ul, U2). 

Following this, the dissolved mucin was further fractionated in our laboratory by isoelectric precipitation of the dissolved mucoprotein fraction from its alkaline solution lowering pH < 3.5, leaving the second dissolved mucin fraction, mucoproteose, in solution (G27). The details of this fractionation technique are shown in Figure 19. 

Pugh et al. (P7) and Mack et al. (Mia, M2), using free boundary electrophoresis, showed that mucoprotein and mucoproteose fractions of the dissolved mucin (G5) had different electrophoretic mobilities mucoprotein fast anodic mobility (5.5-6.9 X cm sec volts ), mucoproteose slow anodic mobility (0.5-1.0 X cm sec volts ) in veronal buffer of pH 9.2 (Fig. 1). Soluble mucus had intermediate mobility of — 3.5 X 10 . It was also noted by Mack et al. (Ml) that the mucoprotein fraction processed from the acid human gastric juice, when nm by itself on Tiselius electrophoresis or when added to acid gastric juice, did not have as fast mobility as the fastest anodic component of the gastric juice, which had a mobility of 7.4-7.S X cm sec volts and which probably, as we know now, corresponded to the complex of pepsin and mucoprotein (see G5). 

Norpoth et al. (N3) compared electrophoretic patterns oi mucoprotein and mucoproteose with those of various other fractions precipitated from the gastric juice. When gastric juice was precipitated by Martin s method (see G5) the gastroglobulin, which is similar to dissolved mucin, showed two peaks which had electrophoretic localization of the glandular mucoprotein and mucoproteose fractions, respectively. Collodion filtration of... 

Kawarada (see BIO) determined polarographic waves of mucus and dissolved mucin fractions, i.e., mucoprotein and mucoproteose. Direct correlation was established between HCl concentration and polarographic mucin waves. In gastric cancer, the polarographic wave of mucoprotein disappeared while that of mucoproteose increased. In peptic ulcer, no significant changes were found. 

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