Circular dichroism (CD) is based on measuring the differential absorption of left- and right-handed circularly polarised light by optical active compounds at different wave lengths. CD spectroscopy is a sensitive tool to study secondary structure changes and provides the basis for the conformational analysis of macromolecules.
The method can be used for the determination of the protein secondary structure (α-helix, β-structure, β-turns) and nucleic acid conformation. Another application of CD spectroscopy is the examination of protein/nucleic acid stability (folding, unfolding ,refolding) under the effect of different factors (pH, denaturants, temperature) and the calculation of thermodynamic parameters related to these processes.
The Jasco–815 spectrometer was purchased with support from the Heidelberg Molecular Life Sciences (HMLS) progamme, and can be accessed by all HMLS member institutes.