title: Evaluation of Structure, Chaperone-Like Activity and Allergenicity of Reduced Glycated Adduct of Bovine β-casein.
abstract: Milk has a potent reducing environment with an important quantity of sugar levels. In the current study β-casein was glycated in the presence of D-glucose and sodium cyanoborohydride as a reducing agent. Then, the reduced glucitol adduct of β-casein was used for the structural and functional analyses using different spectroscopic techniques. The results of fluorescence and far ultraviolet circular dichroism assessments suggest important structural alteration upon non-enzymatic glycation of β-casein. In addition, the chaperone activity, micellization properties and antioxidant activity of this protein were altered upon glucose modification. Also, as a result of reduced glycation, the allergenicity profile of this protein remained largely unchanged. Additional to its energetic and nutritional values, β-casein has important functional properties. The native structure of this protein is important to perform accurately its biological functions. Non-enzymatic glycation under reducing state was capable to alter both structural and functional aspects of β-casein. Due to effective reducing environment and significant quantity of reducing sugar of human milk, similar structural and functional alterations are most likely to occur upon reducing glycation of β-casein in vivo. Also, these changes might be even intensified during chronic hyperglycemia in diabetic mothers.
authors.affiliation: Protein Chemistry Laboratory (PCL), Department of Biology, College of Sciences, Shiraz University, Shiraz, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Yousefi
authors.forename: Leila
authors.initials: L
authors.lastname: Ferdowsi
authors.forename: Zohreh
authors.initials: Z
authors.lastname: Tavaf
authors.forename: Tanaz
authors.initials: T
authors.lastname: Sadeghian
authors.forename: Ali M
authors.initials: AM
authors.lastname: Tamaddon
authors.forename: Mozhgan
authors.initials: M
authors.lastname: Moghtaderi
authors.forename: Zahra
authors.initials: Z
authors.lastname: Pourpak
mesh_terms: D000485:Allergens / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism; D000818:Animals; D002364:Caseins / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism*; D002417:Cattle; D002675:Child, Preschool; D002942:Circular Dichroism; D006031:Glycosylation; D006801:Humans; D007073:Immunoglobulin E / Q000378:metabolism; D007223:Infant; D008823:Micelles; D008892:Milk / Q000737:chemistry / Q000276:immunology*; D011487:Protein Conformation; D017433:Protein Structure, Secondary
chemical_list: D000485:Allergens; D002364:Caseins; D008823:Micelles; D007073:Immunoglobulin E
keywords: allergenicity; chaperone; reduced glycation; structure; β-casein