title: Mass spectrometry detection and reduction of disulfide adducts between reducing agents and recombinant proteins with highly reactive cysteines.
abstract: Recombinant proteins with highly reactive thiol groups can form disulfide adducts with reducing agents commonly used in protein purification, such as beta-mercaptoethanol and dithiothreitol. These adducts can interfere with protein-protein or protein-ligand interactions.This report describes the reduction of persistent disulfide adducts between the reducing agents glutathione or beta-mercaptoethanol and the recombinant protein Cyto-MelCAM, which were detected using matrix-assisted laser desorption and ionization (MALDI) mass spectrometry.These adducts were effectively reduced using the trialkylphosphine reducing agent tris(2-carboxyethyl) phosphine hydrochloride.
authors.affiliation: The Wistar Institute, Philadelphia, PA 19104, USA.
authors.forename: G E
authors.initials: GE
authors.lastname: Begg
authors.forename: D W
authors.initials: DW
authors.lastname: Speicher