Related Experiment Video
Updated: Jun 23, 2026

Thermodynamics of Membrane Protein Folding Measured by Fluorescence Spectroscopy
Published on: April 28, 2011
Monitoring protein folding and unfolding pathways through surface hydrophobicity changes using fluorescence and
1Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India.
Abstract:
In the present study we have investigated the characteristics of folding and unfolding pathways of two model proteins, ovalbumin and alpha-lactalbumin, monitored through the changes in surface hydrophobicity using fluorescence and circular dichroism spectroscopy. In the unfolding process, it was observed that ovalbumin and alpha-lactalbumin followed a three state transition pathway involving an intermediate state having high surface hydrophobicity. The intermediate state has also been characterized by circular dichroism spectroscopy, and it was found that the intermediate retained almost the same secondary structure as the native proteins, and therefore it can be referred to as molten globule state. The refolding process was monitored using fluorescence and circular dichroism spectroscopy, and it was observed that the refolding of alpha-lactalbumin was reversible and proceeded through the accumulation of similar type of intermediates as observed during its unfolding pathway. However, on refolding from the guanidine hydrochloride-denatured state, ovalbumin reached a different folded state.
Related Concept Videos
Molecular Chaperones and Protein Folding
The...
Protein Folding
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
Protein Folding
Protein Folding
Protein Dynamics in Living Cells
Fluorescent recovery after photobleaching (FRAP) is a fluorescent-protein-based detection technique used to quantify protein movement rates within the cell. This method exposes a small portion of the cell to an intense laser beam. The laser beam causes permanent photobleaching of the fluorophore-tagged proteins in the exposed region. As the bleached...

