Abstract
1. A high-molecular-weight glycoprotein constitutes over 80% by weight of the total glycoprotein from water-soluble pig colonic mucus. 2. It was isolated from from nucleic acid and non-covalently bound protein by nuclease digestion followed by equilibrium centrifugation in a CsCl gradient. 3. The glycoprotein has the following composition by weight: fucose 10.4%; glucosamine 23.9%; galactosamine 8.3%; sialic acid 9.9%; galactose 20.8%; sulphate 3.0%; protein 13.3%; moisture about 10%. 4. The native glycoprotein has the high mol.wt. of 15 X 10(6). 5. Reduction of the native glycoprotein with 2-mercaptoethanol results in a glycoprotein of mol.wt. 6 X 10(6). 6. Pronase digestion removes 29% of the protein (3% of the glycoprotein) but none of the carbohydrate. 7. The molecular weight of the Pronase-digested glycoprotein is 1.5 X 10(6), which is halved to 0.76 X 10(6) on reduction with 2-mercaptoethanol. 8. The contribution of non-covalent interactions, disulphide bridges and the non-glycosylated peptide core to the quaternary structure of the glycoprotein are discussed and compared with the known structure of pig gastric glycoportein.
Full text
PDF









Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- AMINOFF D. Methods for the quantitative estimation of N-acetylneuraminic acid and their application to hydrolysates of sialomucoids. Biochem J. 1961 Nov;81:384–392. doi: 10.1042/bj0810384. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Allen A., Pain R. H., Robson T. R. Model for the structure of the gastric mucous gel. Nature. 1976 Nov 4;264(5581):88–89. doi: 10.1038/264088a0. [DOI] [PubMed] [Google Scholar]
- Allen A., Snary D. The structure and function of gastric mucus. Gut. 1972 Aug;13(8):666–672. doi: 10.1136/gut.13.8.666. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Allen A. Structure of gastrointestinal mucus glycoproteins and the viscous and gel-forming properties of mucus. Br Med Bull. 1978 Jan;34(1):28–33. [PubMed] [Google Scholar]
- BURTON K. A study of the conditions and mechanism of the diphenylamine reaction for the colorimetric estimation of deoxyribonucleic acid. Biochem J. 1956 Feb;62(2):315–323. doi: 10.1042/bj0620315. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bella A., Jr, Kim Y. S. Rat small intestinal mucin: isolation and characterization of a water-soluble mucin fraction. Arch Biochem Biophys. 1972 Jun;150(2):679–689. doi: 10.1016/0003-9861(72)90086-0. [DOI] [PubMed] [Google Scholar]
- CROFT D. N., LUBRAN M. THE ESTIMATION OF DEOXYRIBONUCLEIC ACID IN THE PRESENCE OF SIALIC ACID: APPLICATION TO ANALYSIS OF HUMAN GASTRIC WASHINGS. Biochem J. 1965 Jun;95:612–620. doi: 10.1042/bj0950612. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Carlson D. M. Structures and immunochemical properties of oligosaccharides isolated from pig submaxillary mucins. J Biol Chem. 1968 Feb 10;243(3):616–626. [PubMed] [Google Scholar]
- Chambers R. E., Clamp J. R. An assessment of methanolysis and other factors used in the analysis of carbohydrate-containing materials. Biochem J. 1971 Dec;125(4):1009–1018. doi: 10.1042/bj1251009. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Clarke A. E., Denborough M. A. The interaction of concanavalin A with blood-group-substance glycoproteins from human secretions. Biochem J. 1971 Mar;121(5):811–816. doi: 10.1042/bj1210811. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Creeth J. M., Denborough M. A. The use of equilibrium-density-gradient methods for the preparation and characterization of blood-group-specific glycoproteins. Biochem J. 1970 May;117(5):879–891. doi: 10.1042/bj1170879. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Creeth J. M., Pain R. H. The determination of molecular weights of biological macromolecules by ultracentrifuge methods. Prog Biophys Mol Biol. 1967;17:217–287. doi: 10.1016/0079-6107(67)90008-9. [DOI] [PubMed] [Google Scholar]
- Forstner J. F., Jabbal I., Forstner G. G. Goblet cell mucin of rat small intestine. Chemical and physical characterization. Can J Biochem. 1973 Aug;51(8):1154–1166. doi: 10.1139/o73-152. [DOI] [PubMed] [Google Scholar]
- Gorbach S. L. Intestinal microflora. Gastroenterology. 1971 Jun;60(6):1110–1129. [PubMed] [Google Scholar]
- Hill H. D., Jr, Reynolds J. A., Hill R. L. Purification, composition, molecular weight, and subunit structure of ovine submaxillary mucin. J Biol Chem. 1977 Jun 10;252(11):3791–3798. [PubMed] [Google Scholar]
- Hough L., Jones J. V. Human gastric mucosa. I. The preparation of a glycopolypeptide and some aspects of its structure. Carbohydr Res. 1972 Jun;23(1):1–16. doi: 10.1016/s0008-6215(00)81571-2. [DOI] [PubMed] [Google Scholar]
- Inoue S., Yosizawa Z. Purification and properties of sulfated sialopolysaccharides isolated from pig colonic mucosa. Arch Biochem Biophys. 1966 Nov;117(2):257–265. doi: 10.1016/0003-9861(66)90410-3. [DOI] [PubMed] [Google Scholar]
- Kristiansen T., Porath J. Studies on blood group substances. I. Purification of active material from hog gastric mucin by specific precipitation with Vicia cracca phytohemagglutinin. Biochim Biophys Acta. 1968 Jun 24;158(3):351–357. [PubMed] [Google Scholar]
- MAHOWALD T. A., NOLTMANN E. A., KUBY S. A. Studies on adenosine triphosphate transphosphorylases. I. Amino acid composition of adenosine triphosphate-adenosine 5'-phosphate transphosphorylase (myokinase). J Biol Chem. 1962 Apr;237:1138–1145. [PubMed] [Google Scholar]
- Press E. M., Piggot P. J., Porter R. R. The N- and c-terminal amino acid sequences of the heavy chain from a pathological human immunoglobulin IgG. Biochem J. 1966 May;99(2):356–366. doi: 10.1042/bj0990356. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Scawen M., Allen A. The action of proteolytic enzymes on the glycoprotein from pig gastric mucus. Biochem J. 1977 May 1;163(2):363–368. doi: 10.1042/bj1630363. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schrager J. The chemical composition and function of gastrointestinal mucus. Gut. 1970 May;11(5):450–456. doi: 10.1136/gut.11.5.450. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Snary D., Allen A., Pain R. H. Conformational changes in gastric mucoproteins induced by caesium chloride and guanidinium chloride. Biochem J. 1974 Sep;141(3):641–646. doi: 10.1042/bj1410641. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Snary D., Allen A., Pain R. H. Structural studies on gastric mucoproteins: lowering of molecular weight after reduction with 2-mercaptoethanol. Biochem Biophys Res Commun. 1970 Aug 24;40(4):844–851. doi: 10.1016/0006-291x(70)90980-0. [DOI] [PubMed] [Google Scholar]
- Snary D., Allen A. Studies on gastric mucoproteins. The isolation and characterization of the mucoprotein of the water-soluble mucus from pig cardiac gastric mucosa. Biochem J. 1971 Aug;123(5):845–853. doi: 10.1042/bj1230845. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Starkey B. J., Snary D., Allen A. Characterization of gastric mucoproteins isolated by equilibrium density-gradient centrifugation in caesium chloride. Biochem J. 1974 Sep;141(3):633–639. doi: 10.1042/bj1410633. [DOI] [PMC free article] [PubMed] [Google Scholar]
- WEIMER H. E., MOSHIN J. R. Serum glyco protein concentrations in experimental tuberculosis of guinea pigs. Am Rev Tuberc. 1953 Oct;68(4):594–602. doi: 10.1164/art.1953.68.4.594. [DOI] [PubMed] [Google Scholar]