title: Dissection of the binding of hydrogen peroxide to trypsin using spectroscopic methods and molecular modeling.
abstract: Studies on the effects of environmental pollutants to protein in vitro has become a global attention. Hydrogen peroxide (H2O2) is used as an effective food preservative and bleacher in industrial production. The toxicity of H2O2 to trypsin was investigated by multiple spectroscopic techniques and the molecular docking method at the molecular level. The intrinsic fluorescence of trypsin was proved to be quenched in a static process based on the results of fluorescence lifetime experiment. Hydrogen bonds interaction and van der Waals forces were the main force to generate the trypsin-H2O2 complex on account of the negative ΔH(0) and ΔS(0). The binding of H2O2 changed the conformational structures and internal microenvironment of trypsin illustrated by UV-vis absorption, fluorescence, synchronous fluorescence, three-dimensional (3D) fluorescence and circular dichroism (CD) results. However, the binding site was far away from the active site of trypsin and the trypsin activity was only slightly affected by H2O2, which was further explained by molecular docking investigations.
authors.affiliation: Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, 27# Shanda South Road, Jinan 250100, Shandong Province, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Song
authors.affiliation: Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, 27# Shanda South Road, Jinan 250100, Shandong Province, PR China.
authors.forename: Zehua
authors.initials: Z
authors.lastname: Yu
authors.affiliation: Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, 27# Shanda South Road, Jinan 250100, Shandong Province, PR China.
authors.forename: Xinxin
authors.initials: X
authors.lastname: Hu
authors.affiliation: Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, 27# Shanda South Road, Jinan 250100, Shandong Province, PR China. Electronic address: rutaoliu@sdu.edu.cn.
authors.forename: Rutao
authors.initials: R
authors.lastname: Liu
mesh_terms: D000818:Animals; D002417:Cattle; D002942:Circular Dichroism; D006861:Hydrogen Peroxide / Q000378:metabolism*; D007700:Kinetics; D008958:Models, Molecular; D062105:Molecular Docking Simulation; D011485:Protein Binding; D017433:Protein Structure, Secondary; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D013057:Spectrum Analysis / Q000379:methods*; D013816:Thermodynamics; D014357:Trypsin / Q000737:chemistry / Q000378:metabolism*
chemical_list: D006861:Hydrogen Peroxide; D014357:Trypsin
keywords: Hydrogen peroxide; Spectroscopy; Toxicity assessment; Trypsin