Microscopic Insight into the Protein Denaturation Action of Urea and Its Methyl Derivatives
作者单位：Center for Ultrafast Science and TechnologySchool of Chemistry and Chemical EngineeringShanghai Jiao Tong University College of Chemistry and Molecular EngineeringPeking University Department of Chemistry and The Ultrafast Optical Processes LaboratoryUniversity of Pennsylvania
会议名称：《中国化学会第五届全国生物物理化学会议（NCBPC5）》
会议日期：2018年
学科分类：0710[理学-生物学] 071010[理学-生物化学与分子生物学] 081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 070303[理学-有机化学] 0703[理学-化学]
关 键 词：cosolvent effect two-dimensional infrared spectroscopy vibrational probes
摘 要：We employ site-specific two-dimensional infrared spectroscopy as well as molecular dynamics simulations to investigate the binding interactions of urea and three of its derivatives,methylurea,1,3-dimethylurea and tetramethylurea,with protein aromatic and polar *** find that（1） urea methylation leads to preferential interactions between the co-solvent molecules and aromatic sidechains with an affinity that increases with the number of methyl groups;（2） interactions with tetramethylurea cause significant dehydration of aromatic sidechains and the effect is most pronounced for tryptophan;and（3） while neither urea nor tetramethylurea shows preferential accumulation around a polar sidechain,the number of hydrogen-bond donors around this sidechain is significantly decreased in the presence of *** together,our findings suggest that these urea derivatives,especially tetramethylurea,can effectively disrupt hydrophobic interactions in ***,tetramethylurea can promote intramolecular hydrogen-bond formation and hence induce-helix folding in peptides,as observed.