title: The photochemical binding of bithionol to soluble proteins and peptides.
abstract: The photochemical reactions of the bacteriocide bithionol (a known photoallergen in man) with soluble proteins and peptides, were investigated. Solutions of human serum albumin (HSA), human gamma-globulin, bovine insulin and poly-L-lysine were irradiated with ultraviolet light of wavelength 313 nm in the presence of [35S]-bithionol and the extent of photochemical (covalent) binding determined. HSA bound at least four molecules of bithionol per molecule of HSA. Bithionol was also found to bind to gamma-globulin to a similar extent; lower levels of binding were achieved with bovine insulin and poly-L-lysine. A bithionol-HSA photoadduct was treated with cyanogen bromide to determine the selectivity of binding. Fractionation after cyanogen bromide treatment showed that bithionol was bound to both major fragments of HSA, with a preference for the N-terminal region of the protein.
authors: Department of Chemistry and Applied Chemistry, University of Wales, College of Cardiff, U.K.
authors: J N
authors: JN
authors: Delahanty
authors: J C
authors: JC
authors: Evans
authors: C C
authors: CC
authors: Rowlands
authors: R U
authors: RU
authors: Pendlington
authors: M D
authors: MD
authors: Barratt
mesh_terms: D001735:Bithionol / Q000032:analysis*; D003488:Cyanogen Bromide; D006801:Humans; D010455:Peptides / Q000032:analysis*; D010636:Phenols / Q000032:analysis*; D010777:Photochemistry; D011485:Protein Binding; D011506:Proteins / Q000032:analysis*; D012709:Serum Albumin / Q000032:analysis; D012995:Solubility; D014466:Ultraviolet Rays; D005719:gamma-Globulins / Q000032:analysis
chemical_list: D010455:Peptides; D010636:Phenols; D011506:Proteins; D012709:Serum Albumin; D005719:gamma-Globulins; D001735:Bithionol; D003488:Cyanogen Bromide