Induced circular dichroism: Designing undergraduate experiments

CHED 1556

Sergei V Dzyuba, s.dzyuba@tcu.edu, Blaine C Campbell, and Christopher M Brown. Department of Chemistry, Texas Christian University, Fort Worth, TX 76219
Induced circular dichroism (ICD) is a phenomenon that stems from the ability of chiral scaffolds to induce asymmetry in molecules that lack an asymmetric center during their specific interaction. Noteworthy, protein folding/misfolding paradigms can potentially be monitored by the binding of small molecules. Therefore, the concept of ICD should be a valuable complement not only to the traditionally taught stereochemical concepts in undergraduate organic courses, but also to biology, chemical biology and life sciences courses.

Conformationally “locked” biomolecular scaffolds, such as cyclodextrins, serve as an appealing starting point for exploring ICD of small chromophores. Various proteins and aggregation-prone peptides can also be used as scaffolds for probing ICD paradigms with small molecules.

Using results of spectroscopic studies from our and other labs, we have compiled a set of ICD experiments, which are based on the interaction of Congo Red, Thioflavin T and other small molecules with cyclodextrins, proteins, and amyloidogenic peptides. Possibilities for introducing these experiments into an upper-level undergraduate curriculum will be discussed.