Ovine submaxillary mucin

Rose M.C., Voter W.A., Sage H., Brown C.F. and Kaufman, B. (1984). Effects of deglyco-sylation on the architecture of ovine submaxillary mucin glycoprotein. J Biol Chem. 259, 3167-3172... 

Treatment of ovine submaxillary mucin with neuraminidase and proteolytic enzymes, releases glycopeptides containing sequences of O-a-D-GalpiVAc-L-Ser-L-Glx-L-Pro-Gly-, 0-a-D-GalpAAc-L-Ser-,0-a-D-Galp Ac-L-Ser-Gly-Gly-(O-a-D-GalpATAc)-L-Thr-L-Glx-, and Gly-(0-a-D-GalpAAc)-L-Ser-L-Ala-. ... 

Two families of antibodies have been found to be generated after immunization of rabbits with ovine submaxillary mucin. In the case of subcutaneous immunization, the immunodominant determinants are the prosthetic N-acetyl-neuraminosyl-2-acetamido-2-deoxy-D-galactopyranosyl and the 2-acetamido-2-deoxy-D-galactopyranosyl groups, but intravenous immunization of the glycoprotein coupled to red blood cells elicits, in addition, antibodies with specificities for the apoprotein. 

The mucous membranes of the gastrointestinal, respiratory, and genitourinary tracts are lined with a variety of mucins, many of which are probably of the Ser-GalNAc and Thr-GalNAc types. These mucins are difficult to purify and detailed structural information has only been obtained for two salivary gland preparations, ovine submaxillary mucin (OSM) and porcine submaxillary mucin (PSM). 

Fig. 4. The major prosthetic group of ovine submaxillary mucin, i.e., W-acetyl-neuraminyl-( 2->6)-A/-acetyl-D-galactosaminyl-serine.

Fig. 12. Biosynthetic pathway for ovine and porcine submaxillary mucins. Prot, protein GalNAc, N-acetyl-n-galactosamine SA, sialic acid Gal, D-galactose OSM, ovine submaxillary mucin PSM, porcine submaxillary mucin. See text for a discussion of this pathway.

Abbreviations OSM, ovine submaxillary mucin PSM, porcine submaxillary mucin. 

GalNAc-protein (sialidase-treated ovine submaxillary mucin) InefiFective with low molecular weight acceptors NAN- (2 6) -GalNAc-protein Submaxillary glands (pork, sheep, bovine) fibroblasts Section V, A... 

GalNAc-protein (sialidase-treated ovine submaxillary mucin)... 

Neisseria meningitidis is a pathogen that causes meningitis in humans. It has an unusual capsular homopolysaccharide that is composed of A -acetyl-D-neuraminic acid. The monosaccharide residue has nine carbons (see Fig. 6.20A). It makes up a family of sugar acids called sialic acids that are N- and 0-substituted derivatives (see Chapter 9). The sialic acids are widely distributed and are primarily found at the ends of the oligosaccharide chains attached to glycoproteins that are especially prevalent in bovine and ovine submaxillary mucins, erythrocytes, and nerve tissues. A -acetyl-D-neuraminic acid is biosynthesized by an aldol condensation of pyruvic acid with N-acetyl-D-mannosamine (see Chapter 10). 

Hill, H. D., Reynolds, J. A., and Hill, R. L., 1977a, Purification, composition, molecular weight, and subunit structure of ovine submaxillary mucin, J. Biol. Chem. 252 3791-3798. 

Murthy, V.L.N., and Horowitz, M. I., 1966, Alkali-reductive cleavage of ovine submaxillary mucin, Carbohydr. Res. 6 266-275. 

Shogren, R., Gerken, T. A., and Jentoft, N., 1989, Role of glycosylation on the conformation and chain dimensions of 0-linked glycoproteins Light-scattering studies of ovine submaxillary mucin. Biochemistry 28 5525-5536. 

Bertolini, M., and Pigman, W., 1967, Action of alkali on bovine and ovine submaxillary mucins, 7. Biol. Chem. lAli Mlb. 

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