Logo image
Water-Centered Interpretation of Intrinsic pPII Propensities of Amino Acid Residues: In Vitro-Driven Molecular Dynamics Study
Journal article

Water-Centered Interpretation of Intrinsic pPII Propensities of Amino Acid Residues: In Vitro-Driven Molecular Dynamics Study

Derya Meral, Siobhan Toal, Reinhard Schweitzer-Stenner and Brigita Urbanc
The journal of physical chemistry. B, v 119(42), pp 13237-13251
22 Oct 2015
PMID: 26418575

Abstract

Amino Acids - chemistry In Vitro Techniques Molecular Dynamics Simulation Water - chemistry
Amino acid residues of unfolded peptides in water sample only a few basins in the Ramachandran plot, including prominent polyproline II-like (pPII) conformations. Dynamics of guest residues, X, in GXG peptides in water were recently reported to be dominated by pPII and β-strand-like (β) conformations, resulting in an enthalpy-entropy compensation at ∼300 K. Using molecular dynamics (MD) in explicit solvent, we here examine pPII and β conformational ensembles of 15 guest residues in GXG peptides, quantify local orientation of water around their side chains through novel water orientation plots, and study their hydration and hydrogen bonding properties. We show that pPII and β ensembles are characterized by distinct water orientations: pPII ensembles are associated with an increased population of water oriented in parallel to the side chain surface whereas β ensembles exhibit more heterogeneous water orientations. The backbone hydration is significantly higher in pPII than in β ensembles. Importantly, pPII to β hydration differences and the solvent accessible surface area of Cβ hydrogens both correlate with experimental pPII propensities. We propose that pPII conformations are stabilized by a local, hydrogen-bonded clathrate-like water structure and that residue-specific intrinsic pPII propensities reflect distinct abilities of side chains to template this water structure.

Metrics

11 Record Views
36 citations in Scopus

Details

UN Sustainable Development Goals (SDGs)

This publication has contributed to the advancement of the following goals:

#3 Good Health and Well-Being

InCites Highlights

Data related to this publication, from InCites Benchmarking & Analytics tool:

Collaboration types
Domestic collaboration
International collaboration
Web of Science research areas
Biophysics
Chemistry, Physical
Logo image