title: Comprehensive spectroscopic probing the interaction and conformation impairment of bovine serum albumin (BSA) by herbicide butachlor.
abstract: Butachlor is an effective herbicide to deal with undesired weeds selectively and is used at high levels in Asian countries. However, its interaction and impairment effect on BSA was still not clear. In this study, we investigated the interaction between butachlor and bovine serum albumin (BSA) by multi-spectroscopic methods including UV absorption, circular dichroism (CD) spectra, Fourier transform infrared (FTIR) spectra and fluorescence spectra under physiological conditions (pH=7.4). The results revealed that there was a static quenching of BSA induced by butachlor stemmed from the formation of complex. Based on thermodynamic data, the interaction of butachlor with BSA was due to happen, and van der Waals force as well as hydrogen bond were the major forces contributed to the interaction. The binding constant Kb and number of binding site of butachlor with BSA were 5.158×10(5) and 1.372 at 303K, respectively. The distance r between donor (BSA) and acceptor (butachlor) was 0.113nm, obtained according to the Förster theory. The results revealed that butachlor induced conformational changes in BSA but the secondary structure of BSA was still retained. In addition, the microenvironment around chromophore residues of BSA, for example, tryptophan, changed as well, resulting from the formation of more hydrogen bonds.
authors.affiliation: College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, China.
authors.forename: Xiaoyi
authors.initials: X
authors.lastname: Liu
authors.affiliation: College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, China.
authors.forename: Zhaoxing
authors.initials: Z
authors.lastname: Ling
authors.affiliation: College of Atmospheric Science, Lanzhou University, Lanzhou, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Zhou
authors.affiliation: College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, China.
authors.forename: Farooq
authors.initials: F
authors.lastname: Ahmad
authors.affiliation: College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, China; Research Center of Analysis and Measurement, Zhejiang University of Technology, Hangzhou, China. Electronic address: yingzhou@zjut.edu.cn.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhou
mesh_terms: D000083:Acetanilides / Q000378:metabolism* / Q000494:pharmacology*; D000818:Animals; D002417:Cattle; D004735:Energy Transfer; D006540:Herbicides / Q000378:metabolism* / Q000494:pharmacology*; D011485:Protein Binding; D011487:Protein Conformation / Q000187:drug effects; D012710:Serum Albumin, Bovine / Q000737:chemistry* / Q000378:metabolism*; D013057:Spectrum Analysis; D013816:Thermodynamics
chemical_list: D000083:Acetanilides; D006540:Herbicides; D012710:Serum Albumin, Bovine; C054409:butachlor
keywords: Bovine serum albumin (BSA); Butachlor; Herbicide; Interaction; Pesticide; Spectroscopic method