With this award from the Chemistry Major Research Instrumentation Program, Professor Michael Nichols from University of Missouri Saint Louis will acquire a temperature-controlled, stopped-flow circular dichroism (CD) spectropolarimeter with absorbance and fluorescence capabilities and temperature control system as well as a scanning emission monochromator. The proposal is aimed at enhancing research and education at all levels, especially in areas such as (a) early stages of protein folding and self-assembly; (b) protein self-assembly at the air-water interface; (c) transferrin iron release, (d) structural aspects of hormone sensitive lipase; (e) mutational studies of proteins involved in auxin homeostasis; (f) studies of Puf proteins mutants; (g) DNA-ligand interactions; (h) deoxyribozymes and DNA aptamers; (i) structural features of nucleic acid complexes; (j) peptide-based synthetic ion channels; (k) carbohydrate anomeric assignment, and (l) chirality-at-metal complexes.
A circular dichroism spectrophotometer will produce spectral data that provide information on molecular structure and especially the conformations of bio-molecules such as nucleic acids, proteins, and enzymes. The principle measurement is based on differential absorption of left and right circularly polarized light by optically active samples such as those in the double helix of DNA. The stop-flow system allows rapid mixing of samples allowing the acquisition of real time data for the study of chemical kinetics. In general, in a stopped flow spectrometer the enzymatic reaction is initiated by opening of valves followed by injection of the enzyme and substrate. The quantities mixed are controlled by the action of the enzyme, substrate, and stop syringe plungers. The instrument will provide research and laboratory training in analytical techniques that allow measurement of physical properties of organic and inorganic molecules to graduate and undergraduate students as well as postdoctoral fellows. The CD spectrophotometer will be integrated into training of students in Chemistry and Biochemistry for the study of intermolecular interactions, geometric isomers and protein structure.
