I found the following article on the internet that supports the statement that the invertase enzyme form the source saccharomyces cerevisiae can be inactivated 45 to 70 °C.
Effect of temperature and pressure on yeast invertase stability: a kinetic and conformational study
- Dominique Cavaille,
- Didier Combes
- INSA, Centre de Bioingénierie Gilbert Durand (URA CNRS 544, LA INRA), Complexe Scientifique de Rangueil, 31077 Toulouse Cedex, France
Kinetics of the temperature- or pressure-induced denaturation of invertase from Saccharomyces cerevisiae were obtained in the temperature range 45–70°C and in the pressure range 500–650 MPa. The investigation was done by measuring the residual activities after cooling or pressure release and the intrinsic fluorescence of aromatic amino-acids (tyrosine and tryptophan) upon excitation at 277 nm. The residual activity decreased exponentially as a function of time incubation according to a biphasic model either with pressure or temperature, whereas the fluorescence emission indicated a difference between these two parameters. When the enzyme was subjected to thermal treatment, the fluorescence of tyrosine and tryptophan decreased slowly, while after high-pressure treatment, these aromatic residues become more exposed to the aqueous solvent during unfolding, giving rise to a large decrease in fluorescence in the 330–340 nm region. Moreover, in the latter case, an enhancement of light scattering intensity showed changes in protein-protein interactions.
- Invertase; Irreversible denaturation;High pressure;Thermal deactivation;Intrinsic fluorescence
Reference Link: http://www.sciencedi...16816569500145X
Edited by Creative86, 25 November 2013 - 09:37 AM.