Alkali induced unique partially folded state of bovine serum albumin: qualitative and quantitative insights

November 13, 2019

Title

Alkali induced unique partially folded state of bovine serum albumin: qualitative and quantitative insights

Author

P. Prasanthan, N. Kishore

Year

2019

Journal

International Journal of Food Science & Technology

Abstract

Qualitative and quantitative understanding of partially folded states of protein is essential in gaining deeper insights into folding pathways. We have observed a partially folded state of bovine serum albumin (BSA) in the presence of 2,2,2-trifluoroethanol at pH 11.2 which does not resembles the properties of the molten globule state. ThT, a frequently used marker for protein fibrils have two order of greater affinity towards the intermediate state at pH 11.2 compared to native BSA at pH 7.4. Surprisingly, the binding of ANS with this partially folded state is weaker than that of native state of BSA. Combined fluorescence, circular dichroism spectroscopy and isothermal titration calorimetric studies indicate that for such partially folded state, ThT is a better marker compared to ANS. The results have highlighted the importance of dyes like ThT in characterizing partilally folded states of protein which might appear as intermediates in the funnel moldel describing the protein folding pathway.

Instrument

V-550, J-810

Keywords

Absorption, Quantitation, Circular dichroism, Secondary structure, Tertiary structure, Chemical stability, Protein folding, Biochemistry