title: Binding of the veterinary drug tetracycline to bovine hemoglobin and toxicological implications.
abstract: Tetracycline (TC) is a widely used veterinary drug in animal breeding and fishery. Because of its low bioavailability, the TC residue extensively exists in the environment (e.g. soils, lakes and rivers), which can enter the human body, being potentially harmful. Hemoglobin (Hb) is a protein responsible for oxygen carrying in the vascular system of animals. The aim of this study was to investigate the interaction of bovine hemoglobin (BHb) with TC through spectroscopic and molecular modeling methods. The experimental results revealed that TC can interact with BHb with one binding site to form a TC-BHb complex, mainly through van der Waals interactions and hydrogen bonds. The UV-visible absorption, synchronous fluorescence, and circular dichroism (CD) results revealed that the binding of TC can cause conformational and some microenvironmental changes of BHb, which may affect BHb physiological functions. The synchronous fluorescence experiment disclosed that TC binds into BHb central cavity, which was verified by molecular modeling study. The work contributes to clarify the molecular mechanism of TC toxicity in vivo.
authors.affiliation: a State Key Laboratory of Urban Water Resource and Environment , Harbin Institute of Technology , Harbin , PR China.
authors.forename: Zhenxing
authors.initials: Z
authors.lastname: Chi
authors.forename: Rutao
authors.initials: R
authors.lastname: Liu
authors.forename: Hong
authors.initials: H
authors.lastname: You
authors.forename: Donglin
authors.initials: D
authors.lastname: Wang
mesh_terms: D000818:Animals; D001665:Binding Sites; D002417:Cattle; D002942:Circular Dichroism; D005453:Fluorescence; D006454:Hemoglobins / Q000737:chemistry* / Q000378:metabolism*; D008958:Models, Molecular; D062105:Molecular Docking Simulation; D011487:Protein Conformation; D013056:Spectrophotometry, Ultraviolet; D013752:Tetracycline / Q000378:metabolism* / Q000633:toxicity; D013816:Thermodynamics; D019155:Veterinary Drugs
chemical_list: D006454:Hemoglobins; D019155:Veterinary Drugs; D013752:Tetracycline
keywords: Hemoglobin; molecular modeling; multispectroscopic techniques; toxicity evaluation; veterinary drug residue