Articles written in Journal of Biosciences
Volume 2 Issue 3 September 1980 pp 227-233
Intestinal brush border proteins consist of an enzymatically active hydrophilic moiety attached to a hydrophobic tail. Papain dissociates the hydrophilic part by cleaving off the hydrophobic tail, whereas the detergentTriton X-100 solubilizes the whole molecule. Denaturation by 8 M urea or 4 M guanidinium chloride does not alter the structure of the papain-solubilized enzyme. An appreciable alteration of the structure of detergent-solubilized enzyme was observed on denaturation. The difference spectra of Triton X-100 (1%)—solubilized enzyme and its urea denatured form shifts and intensifies, with increase in the concentration of the denaturant with an isobestic point at 252 nm. A new band at 280 nm also appears at 4 M urea concentration. Papain-solubilized glucoamylase has an ∞ -helical conformation in solution unlike the detergentsolubilized fraction. An elongated structure for the papain solubilized enzyme is inferred from the urea denaturation studies and from molecular weight determinations.
Volume 13 Issue 2 June 1988 pp 153-158
Brush border membrane trehalase was purified from monkey small intestine by a procedure which includes solubilisation by Triton X-100, ammonium sulphate fractionation, and chromatography on DE-52 and hydroxyapatite. The purified enzyme had a specific activity of 11 units/mg protein and was purified 140-fold. The enzyme showed a single protein band on Polyacrylamide gel electrophoresis. It had a
Volume 15 Issue 4 December 1990 pp 377-388
Trehalase found to be associated with the brush border membrane vesicles and the Ca2+ aggregated basolateral membrane vesicles were purified to homogeneity. They were found to differ in their molecular weight, subunit structure, heal stability, N-terminal residues, amino acid composition and also the active site residues. Chemical modification showed the presence of a histidine and tyrosine at the active site of brush border membrane vesicle trehalase and two histidines at the active site of basolateral membrane vesicle.