Circular dichroism

Contact : Bruno BARON

PFBMI has a circular dichroism instrument (Aviv 215) equipped with accessories allowing the measure  of total fluorescence or a computer driven titrator usable for addition of ligand or other chemical compunds, and a more ancient device(Jobin-Yvon CD6) equippedwith a stopped-flow accessory (Bio-Logic)
Circular dichroism study of  macromolecules gives insight into their spatial arrangements.  In particular for proteins, it allows to analyse their secondary (far UV, i.e.180-260 nm) and tertiary (near UV, i.e.250-330 nm) folding.
Circular dichroism in near UV
Circular dichroism in far UV

Thermal stability of folded molecules can be determined by performing température scans on the sample. Similarly, conformational stability of a molecule and structural changes induced by complex formation can be checked at  constant  temperature by adding step by step chemical denaturation agents or specific ligands using the computer driven titrator. Finaly, kinetic studies can be performed using a specific accessory allowing fast mixing (“stopped-flow").
Thermal denaturation monitored by far UV analysis