Abstract
Mucus glycoproteins from newborn and adult rat small intestine were radiolabelled in vivo with Na2 35SO4 and isolated from mucosal homogenates by using Sepharose 4B column chromatography followed by CsCl-density-gradient centrifugation. Non-covalently bound proteins, lipids and nucleic acids were not detected in the purified glycoproteins. Amino acid, carbohydrate and sulphate compositions were similar to chemical compositions reported for other intestinal mucus glycoproteins, as were sedimentation properties. There were, however, important differences in the chemical and physical characteristics of the mucus glycoproteins from newborn and adult animals. The buoyant density in CsCl was higher for the glycoproteins from newborn rats (1.55 g/ml versus 1.47 g/ml). On sodium dodecyl sulphate/polyacrylamide/agarose-gel electrophoresis, the glycoprotein from newborn rats had a greater mobility than the adult-rat sample. Although both preparations had similar general amino acid compositions, variations were observed for individual amino acids. The total protein content was greater in the glycoprotein from newborn animals (27%, w/w, versus 18%, w/w). The molar ratio of carbohydrate to protein was less in the newborn, primarily owing to a decreased fucose and N-acetylgalactosamine content. Comparison of the molar ratio of fucose and sialic acid to galactose for both glycoproteins demonstrated a reciprocal relationship similar to that described by Dische [(1963) Ann. N.Y. Acad. Sci. 106, 259-270]. The sulphate content was greater in the glycoprotein from newborn rats (5.5%, w/w, versus 0.9%, w/w). Both had similar sedimentation coefficients in a dissociative solvent. These results suggest an age-related difference in the types of mucus glycoproteins synthesized by small intestine.
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- 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]
- 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]
- DISCHE Z. Reciprocal relation between fucose and sialic acid in mammalian glycoproteins. Ann N Y Acad Sci. 1963 Mar 30;106:259–270. doi: 10.1111/j.1749-6632.1963.tb16643.x. [DOI] [PubMed] [Google Scholar]
- Etzler M. E., Branstrator M. L. Cell surface components of intestinal epithelial cells and their relationship to cellular differentiation. Ciba Found Symp. 1979 Jan 16;(70):51–68. doi: 10.1002/9780470720530.ch4. [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]
- Forstner J. F., Jabbal I., Qureshi R., Kells D. I., Forstner G. G. The role of disulphide bonds in human intestinal mucin. Biochem J. 1979 Sep 1;181(3):725–732. doi: 10.1042/bj1810725. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Galand G., Forstner G. G. Isolation of microvillus plasma membranes from suckling-rat intestine. The influence of premature induction of digestive enzymes by injection of cortisol acetate. Biochem J. 1974 Nov;144(2):293–302. doi: 10.1042/bj1440293. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Henning S. J. Biochemistry of intestinal development. Environ Health Perspect. 1979 Dec;33:9–16. doi: 10.1289/ehp.79339. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jabbal I., Kells D. I., Forstner G., Forstner J. Human intestinal goblet cell mucin. Can J Biochem. 1976 Aug;54(8):707–716. doi: 10.1139/o76-102. [DOI] [PubMed] [Google Scholar]
- Leach B. S., Collawn J. F., Jr, Fish W. W. Behavior of glycopolypeptides with empirical molecular weight estimation methods. 1. In sodium dodecyl sulfate. Biochemistry. 1980 Dec 9;19(25):5734–5741. doi: 10.1021/bi00566a011. [DOI] [PubMed] [Google Scholar]
- Mantle M., Allen A. Isolation and characterization of the native glycoprotein from pig small-intestinal mucus. Biochem J. 1981 Apr 1;195(1):267–275. doi: 10.1042/bj1950267. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Meyer R. A. Comparison of structural glycoproteins from mucus of different sources. Biochim Biophys Acta. 1977 Aug 23;493(2):272–282. doi: 10.1016/0005-2795(77)90183-0. [DOI] [PubMed] [Google Scholar]
- Nelson J. A., Rose L. M., Bennett L. L. Effects of 2-amino-1,3,4-thiadiazole on ribonucleotide pools of leukemia L1210 cells. Cancer Res. 1976 Apr;36(4):1375–1378. [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]
- Snary D., Allen A., Pain R. H. The structure of pig gastric mucus. Conformational transitions induced by salt. Eur J Biochem. 1971 Dec 22;24(1):183–189. doi: 10.1111/j.1432-1033.1971.tb19669.x. [DOI] [PubMed] [Google Scholar]
- Spee-Brand R., Strous G. J., Kramer M. F. Isolation and partial characterization of rat gastric mucous glycoprotein. Biochim Biophys Acta. 1980 Jan 24;621(1):104–116. doi: 10.1016/0005-2795(80)90066-5. [DOI] [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]
- Swann D. A., Mintz G. The isolation and properties of a second glycoprotein (LGP-II) from the articular lubricating fraction from bovine synovial fluid. Biochem J. 1979 Jun 1;179(3):465–471. doi: 10.1042/bj1790465. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Watkins W. M. Blood-group substances. Science. 1966 Apr 8;152(3719):172–181. doi: 10.1126/science.152.3719.172. [DOI] [PubMed] [Google Scholar]

