Our two groups will collaborate to develop chromatography methods to measure amino acid partitioning, to better understand protein stabilities. Current experiments involve liquid oil/water partitioning or crystal diketopiperazine dissolution. But protein cores are neither like liquid oils nor like crystalline dipeptides. We propose 3 chromatographic methods: (1) Ordered-Oil/Water Partitioning Chromatography, in which we will have independent control over the steric constraints and the degree of """"""""liquidness-solidness"""""""" in the oil. (2) Reversed-Phase Hydrogen Bonding Chromatography, in which we will have independent control over the hydrogen bonding capacity in oil and aqueous phases. (3) Peptide Phase Chromatography, in which we will covalently attach peptides, rather than alkyl chains, to silica supports for the partitioning of amino acids from aqueous solvents. We will measure transfer free energies, enthalpies, entropies, and heat capacities for amino acids and peptides. Our goals are: (i) to develop partitioning media that more closely resemble protein cores than current experimental models, and (ii) to dissect hydrogen-bonding and steric components from the transfer thermodynamics. A (4) Theoretical Component will attempt to interpret protein stabilities in terms of these and other experiments. A theory effort will use a fast search strategy (""""""""hydrophobic Zipper"""""""") combined with the partitioning data to model protein stabilities. Our ultimate goal is to use these partitioning studies of amino acids and peptides to help unravel the driving forces underlying protein stabilities.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM048561-05
Application #
2634709
Study Section
Molecular and Cellular Biophysics Study Section (BBCA)
Project Start
1992-09-30
Project End
1998-12-31
Budget Start
1998-01-01
Budget End
1998-12-31
Support Year
5
Fiscal Year
1998
Total Cost
Indirect Cost
Name
Florida State University
Department
Chemistry
Type
Schools of Arts and Sciences
DUNS #
020520466
City
Tallahassee
State
FL
Country
United States
Zip Code
32306
Doyle, C A; Vickers, T J; Mann, C K et al. (2000) Characterization of C18-bonded liquid chromatographic stationary phases by Raman spectroscopy: the effect of mobile phase composition. J Chromatogr A 877:25-39
Doyle, C A; Vickers, T J; Mann, C K et al. (2000) Characterization of C18-bonded liquid chromatographic stationary phases by Raman spectroscopy: the effect of temperature. J Chromatogr A 877:41-59
Bailey, D J; Dorsey, J G (1999) pH effects on micelle-water partitioning determined by micellar electrokinetic chromatography. J Chromatogr A 852:559-71
Lister, A S; Rimmer, C A; Dorsey, J G (1998) Gradient elution electrochromatography with a flow-injection analysis interface. J Chromatogr A 828:105-12
Doyle, C A; Vickers, T J; Mann, C K et al. (1997) Characterization of liquid chromatographic stationary phases by Raman spectroscopy. Effect of ligand type. J Chromatogr A 779:91-112
Siles, B A; Halsall, H B; Dorsey, J G (1995) Retention and selectivity of flavanones on homopolypeptide-bonded stationary phases in both normal- and reversed-phase liquid chromatography. J Chromatogr A 704:289-305
Wheeler, J F; Beck, T L; Klatte, S J et al. (1993) Phase transitions of reversed-phase stationary phases. Cause and effects in the mechanism of retention. J Chromatogr 656:317-33
Hsieh, M M; Dorsey, J G (1993) Accurate determination of log k'w in reversed-phase liquid chromatography. Implications for quantitative structure-retention relationships. J Chromatogr 631:63-78
Dorsey, J G; Khaledi, M G (1993) Hydrophobicity estimations by reversed-phase liquid chromatography. Implications for biological partitioning processes. J Chromatogr 656:485-99
Cole, S R; Dorsey, J G (1993) Effect of stationary phase solvation on shape selectivity in reversed-phase high-performance liquid chromatography. J Chromatogr 635:177-86