Applications of Circular Dichroism Spectroscopy in Studying Protein Folding, Stability, and Interaction

Circular dichroism (CD) spectroscopy has been extensively used to determine the structure and folding of proteins. It provides valuable information about the protein folding phenomenon, especially the molten globule or other intermediates of the folding/unfolding pathway. This technique is beneficial in characterizing protein obtained via recombinant techniques or isolated from tissues. In addition, the effect of mutations on the folding and conformational stability of the protein can be readily assessed using CD spectroscopy. Unlike X-ray crystallography and NMR spectroscopy, the two primary powerful structure determination techniques, the ease and the requirement of low protein concentrations, make CD spectroscopy a desirable and demanding method of choice. This chapter discusses applications of CD spectroscopy in measuring protein structure and stability. The CD spectroscopic investigation of conformational changes and protein stability studied through steady-state and time-resolved CD measurements have been further highlighted. This chapter will provide a better understanding of CD spectroscopy and its uses in biomolecular studies.