Thermodynamic exploration of eosin-lysozyme binding: A physical chemistry and biochemistry laboratory experiment

CHED 445

Andrew J. Huisman, huisman@wisc.edu1, Lydia R. Hartsell, lydia.hartsell@hope.edu2, Brent P. Krueger, kruegerb@hope.edu2, and Michael J. Pikaart2. (1) Department of Chemistry, University of Wisconsin - Madison, Rm 4339, 1101 University Ave, Madison, WI 53706, (2) Department of Chemistry, Hope College, 35 E 12th St, Holland, MI 49423
We have developed a modular pair of laboratory experiments for use both in undergraduate physical chemistry and biochemistry. Both laboratories examine the thermodynamics of the binding of a small molecule, eosin, to the protein lysozyme. The assay for binding is the quenching of lysozyme fluorescence by eosin through resonant energy transfer. In both experiments, students measure fluorescence quenching at constant lysozyme concentration as a function of added eosin and determine the dissociation constant and ΔG for binding. In the physical chemistry experiment, students repeat the fluorescence measurements at several temperatures to determine the temperature-dependence of ΔG, and therefore ΔH and ΔS as well. This pair of laboratories represents an interdisciplinary module in which students in different courses examine the same system, but from different perspectives and with different emphases.
 

Undergraduate Research Poster Session: Chemical Education
11:00 AM-1:00 PM, Monday, March 26, 2007 Hyatt Regency Chicago -- Riverside Center, Poster

Division of Chemical Education

The 233rd ACS National Meeting, Chicago, IL, March 25-29, 2007