The reversible denaturation of protein disulfide isomerase proceeds through intermediates that are stabilized by interaction with guanidine hydrochloride. At pH 7.5, the equilibrium denaturation by urea is completely reversible and the transition can be reasonably well-described by a two-state model involving only native and denatured forms. In comparison, the equilibrium denaturation by guanid...

Banana lectin (BL) is a homodimeric protein categorized among jacalin-related family of lectins. The effect of acidic pH was examined on conformational stability of BL by using circular dichroism, intrinsic fluorescence, 1-anilino-8-napthalene sulfonate (ANS) binding, size exclusion chromatography (SEC) and dynamic light scattering (DLS). During acid denaturation of BL, the monomerization of na...

A cobalt (III)-protoporphyrin IX complex of horse globin (cobaltiglobin) has been prepared and its stability toward acid denaturation determined. Unlike iron(II1) protoporphyrin, which combines with. globin to give ferrihemoglobin, cobalt(II1) protoporphyrin combines with globin to give a complex which experimentally resembles an internal ferrihemichrome in which the heme is attached to the pro...

The thermal denaturation and aggregation of the HbGp, in the oxy- and cyanomet-forms, was investigated by DSC, AUC, DLS, optical absorption and CD, in the pH range from 5.0 to 7.0. Oxy-HbGp has a denaturation process partially reversible and dependent on the temperature. DSC melting curve is characterized by a single peak with T(c) value of 333.4 ± 0.2K for oxy-HbGp, while two peaks with T(c) v...

The coagulation of isoelectric egg albumin solutions, on exposure to ultraviolet radiation, involves three distinct processes, (1) the light denaturation of the albumin molecule, (2) a reaction between the light denatured molecule and water which may be similar to heat denaturation but occurs at a lower temperature, and (3), the flocculation of the denatured molecules to form a coagulum. The li...

chemical denaturation and thermal denaturation of13-lactoglobulin a (f3 — lga) in the absenceand presence of various concentrations sugar osmolytes and polyols were measured bymonitoring changes in the absorption coefficients at ph 2.0. it has been observed that agd°(h20), (gibbs free energy change in absence of denaturant at 25 °c) of f3-1ga in the presenceof 10% (w/v) trehalose, sucrose, sorb...

thermal denaturation of a-lactalbumin in the absence and presence of various concentrations of sucrose,sorbitol, glucose and galactose as sugar osmolytes were measured by monitoring changes in the absorptions thatcarried out in a lambd 35 uv-vis double beam spectrophotometer at ph 6.0. these measurements gave valuesof t., (midpoint of denaturation), ah., (enthalpy change at t.), and acp (consta...

Concentrated solutions of whey proteins (WPC) were prepared from sweet whey by ultrafiltration technique, and stored at – 18°C up to three months. Denaturation degree and viscosity of WPC solutions were assessed. Denaturation degree of whey protein solutions increased significantly (P<0.05) as affected by duration of frozen storage and protein content. The highest degree of denaturation was fou...