title: Molecular origin of the self-assembled morphological difference caused by varying the order of charged residues in short peptides.
abstract: In order to understand how microscopic molecular interactions between short peptides determine their mesoscopic self-assembled morphology, we studied the microscopic assembled structures of the short peptides I4K2 and KI4K, which have the same amino acid composition but different sequences, by using all-atom replica exchange molecular dynamics simulation. We found that, at room temperature, the difference in amino acid sequence does not apparently alter their strong propensity of forming β-sheets but does strongly affect their assembled stable structures and their appearance probabilities. These differences result from the competition between the electrostatic and hydrophobic interactions among the side chains of the molecules, which are linked up by hydrogen bonds formed between neighboring peptide backbones. Our simulation results not only reveal the molecular origin of the self-assembled morphological difference between I4K2 and KI4K but also demonstrate in general the subtle balance between electrostatic, hydrophobic, and hydrogen bonding interactions in short-peptide self-assembly.
authors.affiliation: Centre for Bioengineering and Biotechnology, China University of Petroleum (East China) , 66 Changjiang West Road, Qingdao 266580, China.
authors.forename: Li
authors.initials: L
authors.lastname: Deng
authors.forename: Peng
authors.initials: P
authors.lastname: Zhou
authors.forename: Yurong
authors.initials: Y
authors.lastname: Zhao
authors.forename: Yanting
authors.initials: Y
authors.lastname: Wang
authors.forename: Hai
authors.initials: H
authors.lastname: Xu
mesh_terms: D019281:Dimerization; D006860:Hydrogen Bonding; D056004:Molecular Dynamics Simulation; D010455:Peptides / Q000737:chemistry*; D017433:Protein Structure, Secondary; D012997:Solvents / Q000737:chemistry
chemical_list: D010455:Peptides; D012997:Solvents