Modulation of intra- and inter-sheet interactions in short peptide self-assembly by acetonitrile in aqueous solution

	Modulation of intra- and inter-sheet interactions in short peptide self-assembly by acetonitrile in aqueous solution
	Wang, YT
刊名	CHINESE PHYSICS B
	2016
卷号	25 期号:12 页码:128704
关键词	solvent effect peptide self-assembly molecular dynamics simulation
通讯作者	Xu, H (reprint author), China Univ Petr East China, Ctr Bioengn & Biotechnol, Qingdao 266580, Peoples R China. ; Wang, YT (reprint author), Chinese Acad Sci, Inst Theoret Phys, Key Lab Theoret Phys, Beijing 100190, Peoples R China. ; Wang, YT (reprint author), Univ Chinese Acad Sci, Sch Phys Sci, Beijing 100049, Peoples R China.
合作状况	国内
英文摘要	Besides our previous experimental discovery (Zhao Y R, et al. 2015 Langmuir, 31, 12975) that acetonitrile (ACN) can tune the morphological features of nanostructures self-assembled by short peptides KIIIIK (KI4K) in aqueous solution, further experiments reported in this work demonstrate that ACN can also tune the mass of the self-assembled nanostructures. To understand the microscopic mechanism how ACN molecules interfere peptide self-assembly process, we conducted a series of molecular dynamics simulations on a monomer, a cross-beta sheet structure, and a proto-fibril of KI4K in pure water, pure ACN, and ACN-water mixtures, respectively. The simulation results indicate that ACN enhances the intra-sheet interaction dominated by the hydrogen bonding (H-bonding) interactions between peptide backbones, but weakens the inter-sheet interaction dominated by the interactions between hydrophobic side chains. Through analyzing the correlations between different groups of solvent and peptides and the solvent behaviors around the proto-fibril, we have found that both the polar and nonpolar groups of ACN play significant roles in causing the opposite effects on intermolecular interactions among peptides. The weaker correlation of the polar group of ACN than water molecule with the peptide backbone enhances H-bonding interactions between peptides in the proto-fibril. The stronger correlation of the nonpolar group of ACN than water molecule with the peptide side chain leads to the accumulation of ACN molecules around the proto-fibril with their hydrophilic groups exposed to water, which in turn allows more water molecules close to the proto-fibril surface and weakens the inter-sheet interactions. The two opposite effects caused by ACN form a microscopic mechanism clearly explaining our experimental observations.
学科主题	Physics
类目[WOS]	Physics, Multidisciplinary
关键词[WOS]	PARTICLE MESH EWALD ; BETA-SHEET ; MOLECULAR-DYNAMICS ; AMYLOID FIBRIL ; HYDROPHOBIC INTERACTIONS ; ORGANIC LIQUIDS ; FORCE-FIELD ; SOLVENT ; WATER ; NANOTUBES
收录类别	SCI
语种	英语
内容类型	期刊论文
源URL	[http://ir.itp.ac.cn/handle/311006/21230]
专题	计算平台成果
推荐引用方式 GB/T 7714	Wang, YT. Modulation of intra- and inter-sheet interactions in short peptide self-assembly by acetonitrile in aqueous solution[J]. CHINESE PHYSICS B,2016,25(12):128704.
APA	Wang, YT.(2016).Modulation of intra- and inter-sheet interactions in short peptide self-assembly by acetonitrile in aqueous solution.CHINESE PHYSICS B,25(12),128704.
MLA	Wang, YT."Modulation of intra- and inter-sheet interactions in short peptide self-assembly by acetonitrile in aqueous solution".CHINESE PHYSICS B 25.12(2016):128704.