title: The thermodynamics of the unfolding of an isolated protein subdomain. The 255-316 C-terminal fragment of thermolysin.
abstract: Differential scanning calorimetry has been used to study the thermal unfolding of the 255-316 C-terminal fragment of thermolysin. The concentration effect on the calorimetric transitions of the fragment in 0.1 M NaCl and 20 mM phosphate buffer, pH 7.5, shows that it behaves as a highly stable dimer in solution, within the concentration range 0.19-4.55 mg/ml, undergoing a reversible two-state thermal unfolding process. The thermodynamic parameters of unfolding (delta G = 60 +/- 6 kJ/(mol of dimer) at 20 degrees C) are similar to those normally observed for small, compact, globular proteins. This and previous studies [1989, Eur. J. Biochem. 180, 513-518] show that the 255-316 fragment folds into a stable, native-like globular structure.
authors.affiliation: Department of Physical Chemistry, Faculty of Sciences, University of Granada, Spain.
authors.forename: F
authors.initials: F
authors.lastname: Conejero-Lara
authors.forename: V
authors.initials: V
authors.lastname: De Filippis
authors.forename: A
authors.initials: A
authors.lastname: Fontana
authors.forename: P L
authors.initials: PL
authors.lastname: Mateo
mesh_terms: D002152:Calorimetry, Differential Scanning; D004795:Enzyme Stability; D046911:Macromolecular Substances; D010446:Peptide Fragments / Q000737:chemistry*; D017510:Protein Folding; D012996:Solutions; D013816:Thermodynamics; D013820:Thermolysin / Q000737:chemistry*
chemical_list: D046911:Macromolecular Substances; D010446:Peptide Fragments; D012996:Solutions; D013820:Thermolysin