The effect of nucleotides on the structure and thermal stability of ferricytochrome c was studied by differential scanning calorimetry. The association of cytochrome c with ATP and ADP resulted in a decrease in the denaturation temperature of cytochrome c by 7 degrees C and 4 degrees C, respectively, at pH 7.0. AMP did not change the denaturation temperature of cytochrome c at pH 7.0. The ratio...

There is circumstantial evidence that protein denaturation occurs in cells during heat shock at hyperthermic temperatures and that denatured or damaged protein is the primary inducer of the heat shock response. However, there is no direct evidence regarding the extent of denaturation of normal cellular proteins during heat shock. Differential scanning calorimetry (DSC) is the most direct method...

The thermal denaturation of adenosine deaminase (ADA) has been investigated in the presence of sodium n-dodecyl sulphate (SDS) over the temperature range of (293-363K) in 2.5 mM phosphate buffer, pH 6.4 by temperature scanning spectroscopy. The interaction of SDS caused the folding of adenosine deaminanse resulting in a decrease of TH (temperature of minimum solubility), TS<...

The xylanolytic enzyme complex hydrolyzes xylan, and these enzymes have various industrial applications. goal of this work was to characterize the endoxylanases produced by thermophilic fungus Rasamsonia emersonii in solid-state cultivation. Tests were carried out evaluate effects pH, temperature, glycerol phenolic compounds on activity. Thermal denaturation one isolated evaluated. crude extrac...

We examined the seasonal variation in environmentally induced protein damage in natural populations of the intertidal mussel Mytilus trossulus. In order to compare the state of protein pools during seasonal variations in environmental temperature, we used solid-phase immunochemical analysis to quantify ubiquitin conjugate concentrations and relative levels of the stress protein hsp70. The two b...

Protein stability is measured by denaturation: When solvent conditions are changed (e.g., temperature, denaturant concentration, or pH) the protein population switches between thermodynamic states. The resulting denaturation curves have baselines. If the baselines are steep, nonlinear, or incomplete, it becomes difficult to characterize protein denaturation. Baselines arise because the chromoph...

Within a restricted range of pH and protein concentration crystalline chymotrypsinogen undergoes thermal denaturation which is wholly reversed upon cooling. At a given temperature an equilibrium exists between native and reversibly denatured protein. Within the pH range 2 to 3 the amount of denatured protein is a function of the third power of the hydrogen ion activity. The presence of small am...

Effects of pH and milk constituents (milk ultrafiltrate and ~:-casein) on denaturation of fl-lactoglobulin were investigated by a dynamic method based on differential scanning calorimetry. The apparent reaction order of /Ltactoglobulin denaturation by the dynamic method was 2.0 over the pH range of 4.0 to 9.0, which is in fair agreement with results by other investigators using more classical m...