title: Chemical deglycosylation of hen ovomucoid: protective effect of carbohydrate moiety on tryptic hydrolysis and heat denaturation.
abstract: Hen ovomucoid was chemically deglycosylated by treatment with trifluoromethanesulfonic acid at 0 degrees C for 60 min. About 75 mol% of the carbohydrate moiety was removed from the glycoprotein without changing its amino acid composition, and its trypsin inhibitory activity and immunoreactivity with specific antibodies remained unchanged. The deglycosylated ovomucoid was inactivated and degraded easily by an excess amount of trypsin, whereas the native glycoprotein was not. Furthermore, the biological and immunological activities of the deglycosylated ovomucoid were lowered by heat treatment more easily than those of the native ovomucoid. These results suggest that the carbohydrate moiety of ovomucoid contributes to the stability of the ovomucoid molecule against tryptic hydrolysis and heat denaturation.
authors.affiliation: Department of Food Science and Technology, School of Agriculture, Nagoya University, Aichi.
authors.forename: J X
authors.initials: JX
authors.lastname: Gu
authors.forename: T
authors.initials: T
authors.lastname: Matsuda
authors.forename: R
authors.initials: R
authors.lastname: Nakamura
authors.forename: H
authors.initials: H
authors.lastname: Ishiguro
authors.forename: I
authors.initials: I
authors.lastname: Ohkubo
authors.forename: M
authors.initials: M
authors.lastname: Sasaki
authors.forename: N
authors.initials: N
authors.lastname: Takahashi
mesh_terms: D000818:Animals; D000915:Antibody Affinity; D055598:Chemical Phenomena; D002621:Chemistry; D002645:Chickens; D004527:Egg Proteins / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006031:Glycosylation; D006358:Hot Temperature; D006868:Hydrolysis; D008698:Mesylates / Q000494:pharmacology; D010059:Ovomucin / Q000276:immunology / Q000378:metabolism*; D011489:Protein Denaturation; D014357:Trypsin / Q000378:metabolism; D014361:Trypsin Inhibitors / Q000378:metabolism
chemical_list: D004527:Egg Proteins; D008698:Mesylates; D014361:Trypsin Inhibitors; D010059:Ovomucin; D014357:Trypsin; C012077:trifluoromethanesulfonic acid