Time-Dependent pH Scanning of the Acid-Induced Unfolding of Human Serum Albumin Reveals Stabilization of the Native Form by Palmitic Acid Binding

摘要: The most abundant plasma protein, human serum albumin (HSA), is known to undergo several conformational transitions in an acidic environment. To avoid buffer effects and correlate global local structural changes, we developed a continuous acidification method simultaneously monitored the protein changes by both small-angle scattering (SAXS) fluorescence. progressive acidification, based on hydrolysis of glucono-δ-lactone from pH 7 2.5, highlighted multistep unfolding involving putative F form (pH 4) extended flexible conformation < 3.5). profile was extracted component analysis further 3D modeled. effect acid at this intermediate stage assigned rearrangement three domains drifting apart toward more elongated conformation, with partial one outer domains. test stabilizing fatty acids, here palmitic acid, compared process ...