title: Investigation on the interactions of clenbuterol to bovine serum albumin and lysozyme by molecular fluorescence technique.
abstract: Clenbuterol interacting with bovine serum albumin (BSA) or lysozyme (LYS) in physiological buffer (pH 7.4) was investigated by the fluorescence spectroscopy and UV-vis absorption spectroscopy. The results indicated that clenbuterol quenched the intrinsic fluorescence of BSA and LYS via a static quenching procedure. The binding constants of clenbuterol with BSA and LYS were 1.16×10(3) and 1.49×10(3) L mol(-1) at 291 K. The values of ΔH and ΔS implied that hydrophobic and electrostatic interaction played a major role in stabilizing the complex (clenbuterol-BSA or clenbuterol-LYS). In the presence of Fe2+, Fe3+, Cu2+, Mg2+, Ca2+, or Zn2+, the binding constants of clenbuterol to BSA or LYS had no significant differences. The distances between the donor (BSA or LYS) and acceptor (clenbuterol) were 2.61 and 2.19 nm for clenbuterol-BSA and clenbuterol-LYS respectively. Furthermore, synchronous fluorescence spectrometry was used to analyze the conformational changes of BSA and LYS.
authors.affiliation: College of Chemistry, Changchun Normal University, Changchun 130032, PR China. Electronic address: sy_bi@sina.com.
authors.forename: Shuyun
authors.initials: S
authors.lastname: Bi
authors.affiliation: College of Chemistry, Changchun Normal University, Changchun 130032, PR China.
authors.forename: Bo
authors.initials: B
authors.lastname: Pang
authors.affiliation: College of Chemistry, Changchun Normal University, Changchun 130032, PR China.
authors.forename: Tianjiao
authors.initials: T
authors.lastname: Wang
authors.affiliation: College of Chemistry, Changchun Normal University, Changchun 130032, PR China.
authors.forename: Tingting
authors.initials: T
authors.lastname: Zhao
authors.affiliation: College of Chemistry, Changchun Normal University, Changchun 130032, PR China.
authors.forename: Wang
authors.initials: W
authors.lastname: Yu
mesh_terms: D000318:Adrenergic beta-Agonists / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D001665:Binding Sites; D002417:Cattle; D002976:Clenbuterol / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D009113:Muramidase / Q000737:chemistry / Q000378:metabolism*; D012710:Serum Albumin, Bovine / Q000737:chemistry / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D013816:Thermodynamics
chemical_list: D000318:Adrenergic beta-Agonists; D012710:Serum Albumin, Bovine; D009113:Muramidase; D002976:Clenbuterol
keywords: Bovine serum albumin; Clenbuterol; Fluorescence quenching; Lysozyme; Synchronous fluorescence