A simple and effective device for investigating heat-induced denaturation of proteins by electrospray ionization mass spectrometry is described. Results are presented for the denaturation as a function of temperature and solution pH of bovine ubiquitin and bovine cytochrome c. These results are in concert with and extend the earlier results of LeBlanc et al. (Org. Mass Spectrom. 1991, 26, 831)....

Concentrated solutions of whey proteins (WPC) were prepared from sweet whey by ultrafiltration technique, and stored at – 18°C up to three months. Denaturation degree and viscosity of WPC solutions were assessed. Denaturation degree of whey protein solutions increased significantly (P<0.05) as affected by duration of frozen storage and protein content. The highest degree of denaturation was fou...

To eludicate the role in conformational stability of Cys residues buried in the interior of a protein, the thermodynamic properties of denaturation of mutant alpha subunit of Escherichia coli tryptophan synthase, in which Ser, Ala, Val or Gly was substituted for each of the three Cys residues, were analyzed using calorimetry. The mutants were less stable than the wild type, indicating that Cys ...

A new approach to the problem of cold denaturation is presented. It is based on solvent-induced effects operating on hydrophilic groups along the protein. These effects are stronger than the corresponding hydrophobic effects, and they operate on the hydrophilic groups which are plentiful than hydrophobic groups. It is shown that both heat and cold denaturation can be explained by these hydrophi...