A Study was made on the interaction between histon H1 and sodium n-dodecyl sulphate (SDS) in the presence of sodium arsenate inside a phosphate buffer of pH 6.4, using spectroscopy and equilibrium dialysis at 27 °C. The binding data has been used to obtain the gibbs free energy in terms of a theoretical model based on the Wyman binding potential. The binding data hs been analysed...

IN a recent series of publications Northrop [1930, 1, 2; 1931] has advanced very strong evidence that pepsin is a protein. Starting from commercial pepsin, by suitably regulating the pH and precipitating with the aid of magnesium or ammonium sulphate a crystalline product was obtained which had the general properties of a protein. In particular, solutions of this crystalline pepsin were coagula...

OBJECTIVE Present study explores the effect of hot summer period on the glycolytic rate of early post-mortem meat quality of Ghungroo and Large White Yorkshire (LWY) pig and comparative adaptability to high temperature between above breeds by shifting the expression of stress related genes like mono-carboxylate transporters (MCTs) and heat shock proteins (HSPs). METHODS Healthy pigs of two di...

Purified chicken intestinal alkaline phosphatase is active at pH 8 to 9, but becomes rapidly inactivated with change of pH to 6 or less. Also, a solution of the inactivated enzyme at pH 4.5 rapidly regains its activity at pH 8. In the range of pH 6 to 8 a solution of purified alkaline phosphatase consists of a mixture of active and inactive enzyme in equilibrium with each other. The rate of ina...

The insecticidal crystal (Cry) proteins produced by Bacillus thuringiensis undergo several conformational changes from crystal inclusion protoxins to membrane-inserted channels in the midgut epithelial cells of the target insect. Here we analyzed the stability of the different forms of Cry1Ab toxin, monomeric toxin, pre-pore complex, and membrane-inserted channel, after urea and thermal denatur...

The physicochemical and biochemical properties of hemoglobin associated with haptoglobin were compared with those of hemoglobin bour,d by antihemoglobin antibody. The mechanism of enhanced peroxidase activity of hemoglobin bound by haptoglobin was concluded not to be activation but stabilization of hemoglobin at acidic pH by haptoglobin. Haptoglobin protects hemoglobin from denaturation by acid...

Buffer type, pH and ionic strength, as well as the fraction of polyvinylpyrrolidone were optimized for efficient extraction of b-galactosidase from almond seeds. The enzyme was purified up to electrophoretic homogeneity employing (NH4)2SO4 (15–60 %) fractionation, size exclusion and ion-exchange chromatography. Molecular mass of b-galactosidase as estimated by gel filtration and SDS-PAGE was ap...

Bacteriorhodopsin (bR) trimers naturally form two-dimensional hexagonal crystals in purple membrane (PM), which make it very stable. However, the dnaturation of bR was found to occur during a very narrow pH range when the pH was increased above 12.0, as indicated by inactivation of the photochemical cycle observed by flash photolysis kinetic spectra. Here, atomic force microscopy was used to st...

Thermal denaturations of the type 1 DNA polymerases from Thermus aquaticus (Taq polymerase) and Escherichia coli (Pol 1) have been examined using differential scanning calorimetry and CD spectroscopy. The full-length proteins are single-polypeptide chains comprising a polymerase domain, a proofreading domain (inactive in Taq) and a 5' nuclease domain. Removal of the 5' nuclease domains produces...

Guanidinium HCl (GdmHCl), pH, and heat denaturation of the recombinant human stefin B, a low molecular weight protein inhibitor of cysteine proteinases, has been followed by circular dichroism. From the noncoincidence of the transitions in the near and far UV, the existence of stable intermediate states possessing few persistent tertiary interactions but most of the native-like secondary struct...