Abstract
The gelation process of lysozyme in water/tetramethylurea in the presence of salt was investigated as a function of temperature and system composition by rheology, infrared spectroscopy, and microcalorimetry. Times and temperatures of gelation were determined from the variation of the storage (G′) and loss (G″) moduli. It was found that gelation times follow exponential decays with both protein and tetramethylurea (TMU) concentrations and with temperature. The activation energy for the overall process shows a linear dependence on TMU mass fraction. A strongly increased β-sheet content and reduced α-helix occur with the increase of TMU concentration in the binary solvent. Also, a linear decrease of lysozyme denaturation temperature and enthalpy on TMU concentration is found for the TMU mass fraction up to 0.5, above which no denaturation signal can be detected.
Original language | English |
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Pages (from-to) | 443-454 |
Number of pages | 12 |
Journal | Biopolymers |
Volume | 83 |
Issue number | 5 |
Early online date | 26 Jun 2006 |
DOIs | |
Publication status | Published - 5 Dec 2006 |
Keywords
- Differential scanning calorimetry
- Globular protein
- Infrared spectroscopy
- Rheology
- Sol-gel processes
ASJC Scopus subject areas
- General Biochemistry,Genetics and Molecular Biology
- Biochemistry
- Biophysics