EC Number   |
Temperature Stability Minimum [°C] |
Temperature Stability Maximum [°C] |
Reference  |
|---|
   3.2.1.B26 | 75 |
- |
5 h, 17% loss of activity |
326274 |
| 3.2.1.B26 | 85 |
- |
5 h, 43% loss of activity |
326274 |
| 3.2.1.B26 | 85 |
- |
83% residual activity after 5 h |
326274 |
| 3.2.1.B26 | 90 |
- |
low concentrations of the detergent (up to 0.02%) induce slight changes in the enzyme secondary structure, whereas high concentrations cause the alpha-helix content to increase at high temperatures and prevent protein aggregation |
718769 |
| 3.2.1.B26 | 90 |
- |
low concentrations of the SDS (up to 0.02%) induce slight changes in the enzyme secondary structure, whereas high concentrations cause the alpha-helix content to increase at high temperatures and prevent protein aggregation |
718769 |
| 3.2.1.B26 | 100 |
- |
investigation of the activity and conformational dynamics above 100°C. The data indicate a strong correlation between enzyme activity and protein flexibility. In particular, the time-resolved fluorescence data point out that some regions of the protein structure are very sensitive to the temperature increases, gaining a high flexibility degree with temperature. On the other hand, it is also possible to identify local environments of the enzyme structure that still possess a relatively high rigidity at 125°C |
719097 |
| 3.2.1.B26 | -999 |
- |
the fluorescence emission is characterized by a bimodal lifetime distribution, suggesting that the enzyme structure contains rigid and flexible regions, properly located in the macromolecule. The enzyme activity and thermostability appear to be related to the dynamic properties of these regions as evidenced by perturbation studies of the enzyme structure at alkaline pH and by addition of detergents such as SDS. The pH increase affects the protein dynamics with a remarkable loss of thermal stability and activity; these changes occur without any significant variation in the secondary structure as revealed by far-UV dichroic measurements. In the presence of 0.02% (w/v) SDS at alkaline pH, the enzymatic activity and thermostability are recovered. Under these conditions, the conformational dynamics appear to be similar to that evidenced at neutral pH. Further inreases in SDS concentration, at alkaline pH, render the activity and thermostability of beta-glycosidase similar to those observed in the absence of detergent |
721006 |
| 3.2.1.B26 | -999 |
- |
the thermostable enzyme is an interesting model system for the study of protein adaptation to high temperatures. The largest ion-pair network of the enzyme is located at the tetrameric interface of the molecule |
721007 |
| 3.2.1.B26 | 85 |
- |
k(inact): 0.0000061 (wild-type enzyme), 0.00012 (mutant enzyme R488A), 0.00029 (mutant enzyme H489A), 0.00001 (mutant enzyme delHis489) |
721007 |
| 3.2.1.B26 | -999 |
- |
an important role of the sequence segment present only in hyperthermophilic beta-glycosidases, in the thermal adaptation of archaea beta-glycosidases is hypothesized. The thermostabilization mechanism could occur as a consequence of numerous favorable ionic interactions of the 83–124 sequence with the other part of protein matrix that becomes more rigid and less accessible to the insult of thermal-activated solvent molecules |
721008 |
