title: Alpha casein micelles show not only molecular chaperone-like aggregation inhibition properties but also protein refolding activity from the denatured state.
abstract: Casein micelles are a major component of milk proteins. It is well known that casein micelles show chaperone-like activity such as inhibition of protein aggregation and stabilization of proteins. In this study, it was revealed that casein micelles also possess a high refolding activity for denatured proteins. A buffer containing caseins exhibited higher refolding activity for denatured bovine carbonic anhydrase than buffers including other proteins. In particular, a buffer containing α-casein showed about a twofold higher refolding activity compared with absence of α-casein. Casein properties of surface hydrophobicity, a flexible structure and assembly formation are thought to contribute to this high refolding activity. Our results indicate that casein micelles stabilize milk proteins by both chaperone-like activity and refolding properties.
authors.affiliation: Bioengineering Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Sakono
authors.forename: Konomi
authors.initials: K
authors.lastname: Motomura
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Maruyama
authors.forename: Noriho
authors.initials: N
authors.lastname: Kamiya
authors.forename: Masahiro
authors.initials: M
authors.lastname: Goto
mesh_terms: D000818:Animals; D002021:Buffers; D002122:Calcium Chloride / Q000737:chemistry; D002256:Carbonic Anhydrases / Q000737:chemistry; D002364:Caseins / Q000737:chemistry*; D002417:Cattle; D008823:Micelles; D008894:Milk Proteins / Q000737:chemistry*; D018832:Molecular Chaperones / Q000737:chemistry*; D011489:Protein Denaturation; D017510:Protein Folding; D055550:Protein Stability
chemical_list: D002021:Buffers; D002364:Caseins; D008823:Micelles; D008894:Milk Proteins; D018832:Molecular Chaperones; D002256:Carbonic Anhydrases; D002122:Calcium Chloride