Thermodynamics of a molten globule state of human serum albumin by 3-β-hydroxybutyrate as a ketone body

• Published in: International journal of biological macromolecules 2013-03, Vol.54, p.258-263
• Main Authors: Bohlooli, M., Moosavi-Movahedi, A.A., Taghavi, F., Habibi-Rezaei, M., Seyedarabi, A., Saboury, A.A., Ahmad, F.
• Format: Article
• Language: English
• Subjects: 3- β- Hydroxybutyrate; 3-Hydroxybutyric Acid - chemistry; Anilino Naphthalenesulfonates - chemistry; Calorimetry, Differential Scanning; Circular Dichroism; differential scanning calorimetry; DSC; fluorescence; Human serum albumin; Humans; hydrophobicity; Ketone Bodies - metabolism; Ketone body; Light; light scattering; Molten globule; Particle Size; Prolonged incubation; Protein Structure, Secondary; Protein Unfolding; Scattering, Radiation; Serum Albumin - metabolism; Spectrometry, Fluorescence; Spectrophotometry, Ultraviolet; spectroscopy; Thermodynamics; Tryptophan - metabolism
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2012.12.018

► HSA molten globule formation upon 21-incubation days with 3-β-hydroxybutyrate. ► DSC deconvoluted thermograms showed increasing in two energetic domains distance. ► Increased hydrophobicity of modified HSA with 3-β-hydroxybutyrate after 21 days. ► Enhanced size of modified HSA by DLS results. The molten globule (MG) state is an intermediate which is considered as the third thermodynamic state of protein molecules. In this work the effect of incubating human serum albumin (HSA) at physiological condition in the presence of 3-β-hydroxybutyrate for 7, 14, 21 and 35 days were studied by different techniques such as UV/vis, fluorescence and circular dichroism (CD) spectroscopy, differential scanning calorimetry (DSC) and dynamic light scattering (DLS). In this paper, we introduce the MG state for HSA upon 21 days incubation with 3-β-hydroxybutyrate as a ketone body at physiological condition. The results from the HSA sample incubated for 21 days shows a similar secondary structure by CD, more surface hydrophobicity and a little change on tertiary structure by fluorescence, and a larger size by DLS as compared to the native sample or other incubated samples. These results were also confirmed by calculated parameters and DSC deconvoluted thermograms.