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Gordon C. KresheckAdjunct Professor, Chemistry(719) 262-3829 gkreshec@uccs.edu B.S., The Ohio State University (1955) |
Research Associate, Biochemical Laboratories, Nobel Medical Institute (1962-1963); Visiting Scientist, Procter & Gamble Co. (1963); NIH Postdoctoral Research Fellow, Cornell University (1963-1965); Professor of Chemistry and Director of the Center for Biochemical and Biophysical Studies, Northern Illinois University (1965-1997); Resident Research Associate, Argonne National Laboratory (1966); UCCS (1997-current)
Although tremendous advances have been made during recent years in the description of the three-dimensional structure of protein molecules in the crystalline state through the use of X-ray crystallography, our knowledge of the solution properties of these intriguing molecules is still incomplete. Although the types of bonding and forces involved can be identified, an a priori prediction of the way a particular low molecular weight substance binds to a given protein cannot be made. This situation exists despite the importance of such interactions for essential biological processes such as transport across cell walls and membranes, oxygen utilization, and all enzyme catalyzed reactions.
We are attempting to develop various model systems which will allow us to study the interaction of ligands with macromolecules in a systematic way. One such system we studied, micelle formation of surfactants, has been used by others in a description of the thermodynamic basis for the stability of proteins, nucleic acids, and membranes. We have extended these studies to a thermodynamic investigation of the interaction of the same surfactant molecules with synthetic polypeptides and proteins.
More recently, various phospholipids have replaced the surfactant molecules as the lipid component. Interesting differences between the nature of the complex formed in phospholipid "rich" and phospholipid "poor" mixtures have been identified. The former may be more like a model membrane system, whereas the latter may be more like a phospholipid-containing, membrane-bound enzyme.
The methodology involved in such studies varies somewhat with the properties of the system. In many cases, we have been able to use solution calorimetry to determine the enthalpy change and stoichiometry for the binding processes. Either titration or scanning calorimetry is used for this purpose.
Kresheck, G. C. “Isothermal Titration Calorimetry Studies of Neutral Salt Effects on the Thermodynamics of Micelle Formation,” J. Phys. Chem. B 2009, 113, 6732.
Kresheck, G., Wang, Z. "A New Micellar Aqueous Two-Phase Partitioning System (ATPS) for the Separation of Proteins," J. Chromatogr. B 2007, 858, 247.
Kresheck, G. C. "Denaturation of Bovine beta-Lactoglogulin in the Presence of n-Octyl-, Decyl-, and Dodecyldimethylphosphine Oxides," J. Phys. Chem. B 2007, 111, 3550.
Kresheck, G. C. "The temperature dependence of the heat capacity change for micellization of nonionic surfactants," J. Colloid Interface Sci. 2006, 298, 432.
Kresheck, G. C.; Mihelich, J. "Observation of complex thermal transitions for mixed micelle solutions containing alkyldimethylphosphine oxides and phospholipids and the accompanying cloud points," Chemistry and Physics of Lipids 2003, 123, 45.
Volkman, B. F., Zhang, Q., Debabov, D. V., Rivera, E., Kresheck, G. C.; Neuhaus, F. C. "Biosynthesis of D-alanyl-lipoteichoic Acid: The tertiary structure of apo-D-alanyl carrier protein," Biochemistry 2001, 40, 7964.
Kresheck, G. C. "Comparison of the DSC curves obtained for aqueous solutions of nonionic and ionic surfactants," J. Phys. Chem. B 2001, 105, 4380.
Kresheck, G. C. "Interpretation of the differential scanning calorimetry curves for aqueous solutions of three nonionic surfactants," Langmuir 2000, 16, 3067.
Kresheck. G. C. "A calorimetric determination of the standard enthalpy and heat capacity changes that accompany micelle formation for four long chain alkyldimethylphosphine oxides in H2O and D2O solution from 15 to 79o C," J. Amer. Chem. Soc. 1998, 120, 10964.
Kresheck, G. C. "Comparison of the calorimetric and van't Hoff enthalpy of micelle formation for a nonionic surfactant in H2 O and D2O solutions from 15 to 40o C," J. Phys. Chem. B 1998, 102, 6596.
Kresheck, G. C. "Determination of the relative partial molar enthalpy of decyldimethylphosphine oxide in H2O and D2O at 25o C," J. Colloid Interface Sci. 1997, 187, 542; 1998, 203, 231.
Erman, J. E.; Kresheck, G. C.; Vitello, L.B.; Miller, M. "Cytochrome c/cytochrome c peroxidase complex: effect of binding-site mutations on the thermodynamics of complex formation," Biochemistry 1997, 36, 4054.