title: Appraisal of casein's inhibitory effects on aggregation accompanying carbonic anhydrase refolding and heat-induced ovalbumin fibrillogenesis.
abstract: It is well accepted that whole casein and its purified major components, due to their chaperone-like activity, are able to suppress the thermal and chemical aggregation of several substrate proteins. In this study, we set out to determine whether whole and beta-casein are able to prevent (or attenuate) aggregation accompanying refolding of chemically denatured carbonic anhydrase or to recover lost biological activity after its denaturation. Additionally, we showed attenuated heat-induced fibrillar aggregation of egg white ovalbumin in the presence of these commonly occurring unfolded proteins, as molecular chaperones. Also, the extent, rate and order of aggregation, in the presence and absence of aggregation suppressors, were compared. Although beta-casein did not prevent aggregation as strong as whole casein, both chaperones were efficient not only in suppressing the aggregation extent of denatured carbonic anhydrase, but also in delaying elongation process of amyloid fibril formation with no effect on nucleation phase.
authors.affiliation: Department of Pharmacognosy and Biotechnology, Faculty of Pharmacy, P.O. Box 67145-1673, Kermanshah University of Medical Sciences, Kermanshah, Iran. rkhodarahmi@mbrc.ac.ir
authors.forename: Reza
authors.initials: R
authors.lastname: Khodarahmi
authors.forename: Mehdi
authors.initials: M
authors.lastname: Beyrami
authors.forename: Hosnieh
authors.initials: H
authors.lastname: Soori
mesh_terms: D000682:Amyloid / Q000037:antagonists & inhibitors* / Q000737:chemistry; D002256:Carbonic Anhydrases / Q000737:chemistry*; D002364:Caseins / Q000737:chemistry / Q000494:pharmacology*; D006358:Hot Temperature; D007700:Kinetics; D018832:Molecular Chaperones / Q000737:chemistry / Q000494:pharmacology*; D009391:Nephelometry and Turbidimetry; D010047:Ovalbumin / Q000737:chemistry; D011489:Protein Denaturation / Q000187:drug effects; D017510:Protein Folding; D017433:Protein Structure, Secondary; D013050:Spectrometry, Fluorescence
chemical_list: D000682:Amyloid; D002364:Caseins; D018832:Molecular Chaperones; D010047:Ovalbumin; D002256:Carbonic Anhydrases