title: 2-Hydroxy-5-nitrobenzyl bromide as a specific reagent for tryptophan residues in membrane proteins: bacteriorhodopsin as an example.
abstract: The use of 2-hydroxy-5-nitrobenzyl bromide for the modification of tryptophan residues in integral membrane proteins is exemplified by its application to bacteriorhodopsin from Halobacterium halobium. Complete elimination of the unreacted reagent requires delipidation of the sample with detergents and posterior chromatography. This method also allows separation of the modified from the unmodified bacteriorhodopsin molecules. Modified molecules have lost the retinal, and are thus bleached, whereas the unmodified molecules appear to retain all the characteristics of solubilized native bacteriorhodopsin.
authors.affiliation: Departament de Bioquímica i Biologia Molecular, Facultat de Medicina, Universitat Autònoma de Barcelona, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Sabés
authors.forename: J
authors.initials: J
authors.lastname: Torres
authors.forename: M
authors.initials: M
authors.lastname: Duñach
authors.forename: E
authors.initials: E
authors.lastname: Padrós
mesh_terms: D015077:2-Hydroxy-5-nitrobenzyl Bromide; D001436:Bacteriorhodopsins / Q000032:analysis*; D007202:Indicators and Reagents; D008565:Membrane Proteins / Q000032:analysis*; D009596:Nitrophenols; D014364:Tryptophan / Q000032:analysis*
chemical_list: D007202:Indicators and Reagents; D008565:Membrane Proteins; D009596:Nitrophenols; D001436:Bacteriorhodopsins; D015077:2-Hydroxy-5-nitrobenzyl Bromide; D014364:Tryptophan