title: Chaperone activities of bovine and camel beta-caseins: Importance of their surface hydrophobicity in protection against alcohol dehydrogenase aggregation.
abstract: Beta-casein (beta-CN) showing properties of intrinsically unstructured proteins (IUP) displays many similarities with molecular chaperones and shows anti-aggregation activity in vitro. Chaperone activities of bovine and camel beta-CN were studied using alcohol dehydrogenase (ADH) as a substrate. To obtain an adequate relevant information about the chaperone capacities of studied caseins, three different physical parameters including chaperone constant (k(c), microM(-1)), thermal aggregation constant (k(T), degrees C(-1)) and aggregation rate constant (k(t), min(-1)) were measured. Bovine beta-CN displays greater chaperone activity than camel beta-CN. Fluorescence studies of 8-anilino-1-naphthalenesulfonic acid (ANS) binding demonstrated that bovine beta-CN is doted with larger effective hydrophobic surfaces at all studied temperatures than camel beta-CN. Greater relative hydrophobicity of bovine beta-CN than camel beta-CN may be a factor responsible for stronger interactions of bovine beta-CN with the aggregation-prone pre denatured molecular species of the substrate ADH, which resulted in greater chaperone activity of bovine beta-CN.
authors.affiliation: Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran.
authors.forename: Abolfazl
authors.initials: A
authors.lastname: Barzegar
authors.forename: Reza
authors.initials: R
authors.lastname: Yousefi
authors.forename: Ahmad
authors.initials: A
authors.lastname: Sharifzadeh
authors.forename: Michèle
authors.initials: M
authors.lastname: Dalgalarrondo
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Chobert
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Ganjali
authors.forename: Parviz
authors.initials: P
authors.lastname: Norouzi
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Ehsani
authors.forename: Amir
authors.initials: A
authors.lastname: Niasari-Naslaji
authors.forename: Ali Akbar
authors.initials: AA
authors.lastname: Saboury
authors.forename: Thomas
authors.initials: T
authors.lastname: Haertlé
authors.forename: Ali Akbar
authors.initials: AA
authors.lastname: Moosavi-Movahedi
mesh_terms: D000426:Alcohol Dehydrogenase / Q000737:chemistry*; D000595:Amino Acid Sequence; D000817:Anilino Naphthalenesulfonates / Q000737:chemistry; D000818:Animals; D002162:Camelus; D002364:Caseins / Q000737:chemistry*; D002417:Cattle; D004305:Dose-Response Relationship, Drug; D006736:Horses; D008099:Liver / Q000378:metabolism; D008823:Micelles; D018832:Molecular Chaperones / Q000737:chemistry*; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid; D013696:Temperature
chemical_list: C515594:8-anilino-1-naphthalenesulfonic acid; D000817:Anilino Naphthalenesulfonates; D002364:Caseins; D008823:Micelles; D018832:Molecular Chaperones; D000426:Alcohol Dehydrogenase