Abstract

The gal repressor of E. Coli (GalR) regulates transcription from the gal operon. It is a dimeric protein that binds one molecule of inducer, D-galactose, per subunit. The protein is obtained from a bacterial expression system and is often found in inclusion bodies. While investigating renaturation of GalR from inclusion bodies, we became interested in its unfolding properties. Intrinsic tryptophan fluorescence is substantially quenched and its emission peak is red shifted when the protein unfolds in urea. Binding of D-galactose causes significant stabilization against urea induced denaturation. CD measurements will provide an independent measure of GalR unfolding in urea which can be correlated with our fluorescence data.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Center for Research Resources (NCRR)
Type
Biotechnology Resource Grants (P41)
Project #
5P41RR004328-10
Application #
6122031
Study Section
Project Start
1997-08-05
Project End
1998-08-04
Budget Start
Budget End
Support Year
10
Fiscal Year
1997
Total Cost
Indirect Cost

  Institution

Name
Johns Hopkins University
Department
Type
DUNS #
045911138
City
Baltimore
State
MD
Country
United States
Zip Code
21218

  Publications

Jaganaman, Sunil; Pinto, Alex; Tarasev, Michael et al. (2007) High levels of expression of the iron-sulfur proteins phthalate dioxygenase and phthalate dioxygenase reductase in Escherichia coli. Protein Expr Purif 52:273-9
Karantza, V; Freire, E; Moudrianakis, E N (2001) Thermodynamic studies of the core histones: stability of the octamer subunits is not altered by removal of their terminal domains. Biochemistry 40:13114-23
Todd, M J; Gomez, J (2001) Enzyme kinetics determined using calorimetry: a general assay for enzyme activity? Anal Biochem 296:179-87
Griko, Y V; Remeta, D P (1999) Energetics of solvent and ligand-induced conformational changes in alpha-lactalbumin. Protein Sci 8:554-61
Chu, V; Freitag, S; Le Trong, I et al. (1998) Thermodynamic and structural consequences of flexible loop deletion by circular permutation in the streptavidin-biotin system. Protein Sci 7:848-59
Luque, I; Freire, E (1998) Structure-based prediction of binding affinities and molecular design of peptide ligands. Methods Enzymol 295:100-27
Luque, I; Gomez, J; Semo, N et al. (1998) Structure-based thermodynamic design of peptide ligands: application to peptide inhibitors of the aspartic protease endothiapepsin. Proteins 30:74-85
Gomez, J; Semo, N; Freire, E (1998) Structural thermodynamic study of the binding of renin inhibitors to endothiapepsin. Adv Exp Med Biol 436:325-8
Koder, R L; Miller, A F (1998) Overexpression, isotopic labeling, and spectral characterization of Enterobacter cloacae nitroreductase. Protein Expr Purif 13:53-60
Freire, E (1998) Statistical thermodynamic linkage between conformational and binding equilibria. Adv Protein Chem 51:255-79

Showing the most recent 10 out of 86 publications