Preferential Oxidation of Tryptophan Residues in κ-Casein with N-Bromosuccinimide

Reactivity of the tryptophan residues in bovine pancreatic deoxyribonuclease with N-bromosuccinimide.

DNase, containing 3 tryptophan residues, can be inactivated by modification of this amino acid with Nbromosuccinimide. Chromatography of acid hydrolysates shows all three tryptophan residues modified by the time inactivation is complete. However, spectrophotometric measurement indicates that only 2 residues are modified. The discrepancy is due to the unreliability of the spectrophotometric meth...

Tryptophan residues are targets in hypothiocyanous acid-mediated protein oxidation.

Myeloperoxidase, released by activated phagocytes, forms reactive oxidants by catalysing the reaction of halide and pseudo-halide ions with H(2)O(2). These oxidants have been linked to tissue damage in a range of inflammatory diseases. With physiological levels of halide and pseudo-halide ions, similar amounts of HOCl (hypochlorous acid) and HOSCN (hypothiocyanous acid) are produced by myeloper...

Spectrophotometric determination of olanzapine by its oxidation with N-bromosuccinimide and cerium(IV)sulfate.

Three simple spectrophotometric methods have been described for the assay of olanzapine in its pure and pharmaceutical formulations. The direct method (A) is based on the drug oxidation with excess of N-bromosuccinimide in acidic medium and the two indirect methods (B and C) are based on the oxidation of the drug with excess of N-bromosuccinimide and cerium(IV)sulfate, followed by the reaction ...

Flow injection chemiluminescence determination of amino acids by oxidation with N-bromosuccinimide.

The role of tryptophan in structural and functional properties of equinatoxin II.

A pore-forming, cytolytic and lethal polypeptide, equinatoxin II, from the sea anemone Actinia equina, was subjected to oxidation with N-bromosuccinimide to study the role of five present tryptophan residues in structure-function relationships. In the folded toxin molecule, 1-2 tryptophan residues were readily susceptible to oxidation with N-bromosuccinimide, whereas modification of a single re...