title: Spectroscopic studies on the interaction between riboflavin and albumins.
abstract: The interactions between riboflavin (RF) and human and bovine serum albumin (HSA and BSA) were studied by using absorption and fluorescence spectroscopic methods. Intrinsic fluorescence emission spectra of serum albumin in the presence of RF show that the endogenous photosensitizer acts as a quencher. The decrease of fluorescence intensity at about 350 nm is attributed to changes in the environment of the protein fluorophores caused by the ligand. The quenching mechanisms of albumins by RF were discussed. The binding constants and binding site number were obtained at various temperatures. The distance between albumins and RF in the complexes suggests that the primary binding site for RF is close to tryptophan residue (Trp214) of HSA and Trp212 of BSA. The hydration process of albumins has also been discussed.
authors.affiliation: Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, PR China. zhaohongwei@sinap.ac.cn <zhaohongwei@sinap.ac.cn>
authors.forename: Hongwei
authors.initials: H
authors.lastname: Zhao
authors.forename: Min
authors.initials: M
authors.lastname: Ge
authors.forename: Zhaoxia
authors.initials: Z
authors.lastname: Zhang
authors.forename: Wenfeng
authors.initials: W
authors.lastname: Wang
authors.forename: Guozhong
authors.initials: G
authors.lastname: Wu
mesh_terms: D000042:Absorption; D000818:Animals; D001665:Binding Sites; D002417:Cattle; D004735:Energy Transfer; D006801:Humans; D011485:Protein Binding; D012256:Riboflavin / Q000737:chemistry*; D012709:Serum Albumin / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D014364:Tryptophan / Q000737:chemistry
chemical_list: D012709:Serum Albumin; D012710:Serum Albumin, Bovine; D014364:Tryptophan; D012256:Riboflavin