Thermally induced aggregation

Mills, E.N., Huang, L., Noel, T.R., Gunning, A.P., and Morris, V.J. 2001. Formation of thermally induced aggregates of the soya globulin beta-conglycinin. Biochim Biophys Acta 1547(2) 339-350. 

Globular storage proteins generally exhibit remarkable stability, especially thermal stability, which is common for proteins of the cupin superfamily. Globulins all share the tendency to form large thermally induced aggregates (heat-set gels), which form the basis of the widespread utilization of soy protein in foods (Mills et al. 2002). 

Are the irreversible denaturation pathways truly irreversible Thomas and coworkers have demonstrated that the activity of (inactive) oxidized aFGF can be recovered by the addition of the reducing agent dithiothreitol (10). Furthermore, as previously mentioned, various formulation additives have minimized thermally induced aggregation of aFGF. In addition to the physiological implications, these irreversible denaturation pathways also complicate thermodynamic analyses of protein stability, particularly those which rely on van t Hoff analysis of denaturation profiles. 

Kleber, N., Krause, I., lUgner, S., and Hinrichs, J., The antigenic response of P-lactoglobulin is modulated by thermally induced aggregation, Eur. Food Res. Technol, 219, 105-110, 2004. 

In contrast to thermally induced aggregates, isolated aggregates of bevacizumab produced by up to 30 freeze-thaw cycles showed little change in HX kinetics [30]. In this case, thCTe was also no appreciable change in intrinsic tryptophan fluorescence or ANS fluorescence between the freeze-thaw-induced aggregate and the control mAb. Results from HX-MS analysis in this study correlated well with fluorescence measurements, and the fluorescence results were consistent with observations in a complementary freeze-thaw and thermally induced aggregate study with another mAb [57]. 

Figure 7 shows the effect of PEG on the solubility of BSA in water before and after thermally induced aggregation at pH 5.4. The dependences obtained proved to be rectilinear. Extrapolation of this dependence to = 0 gives the value for the effective activity of the protein in its saturated solution (log [30]. 

The results obtained show that thermally induced aggregation of BSA does not affect appreciably on the activity of saturated BSA solutions, and therefore solvent quality of the BSA before and after the limited aggregation is almost the same. 

Schuler, J., J. Frank, W. Saenger, and Y. Georgahs. 1999. Thermally induced aggregation of human transferrin receptor studied by light-scattering techniques. Biophysical Journal 77 (2) 1117-1125. 

Fig. 16 The thermal response of different polymeric structures based on PVCL and the amphiphilic macromonomer MAC11EO42. Left Shrinking of the grafted PVCL microgel. Right Heat-induced aggregation of the graft copolymer and formation of a mesoglobule [181]...

The preparational route for these luminescent ceramics follows the known ceramic technologies [12,13]. They are generated by thermally induced diffusion densification of powder aggregates below their melting temperature, which is referred to as sintering. As a consequence of this preparational route the properties of such ceramic scintillators are not only determined by the host lattice and the dopants (like the luminescent activator), but additionally by the processing technique. 

Thermally-induced phase separation has been applied to the production of polysilane foams. Variation of polymer concentration, solvent type, and cooling rate have been used to refine the macrostructure. Both these membrane production methods rely on the formation of aggregates of controlled size and shape as discussed in the previous section. 

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