6533b857fe1ef96bd12b44bf

RESEARCH PRODUCT

DFT study of N–H···O hydrogen bond between model dehydropeptides and water molecule

Aneta BuczekMałgorzata A. Broda

subject

Alaninehydrogen bondB3LYPHydrogen bondStereochemistryChemistryBent molecular geometryLow-barrier hydrogen bonddehydroamino acidsBiophysicsDihedral angleCondensed Matter PhysicsDFTM06-2XMoleculeDensity functional theoryPhysical and Theoretical ChemistryMolecular BiologyPolyproline helix

description

The strength of the hydrogen bond formed between a water molecule and two α,β-dehydroalanine derivatives including Ac-ΔAla-NMe2 (1) and Ac-ΔAla-NHMe (2) in comparison with standard amino acid Ac-Ala-NMe2 (3) is studied by density functional theory (with M06-2X and B3LYP functionals). Calculations were conducted for two different conformations of the peptides: extended (C5) and bent (β) with polyproline II backbone dihedral angles. The obtained results show that both dehydro and standard peptides in bent conformation form stronger hydrogen bonds with water than in the extended ones. Moreover, due to higher polarity of the N–H group of α,β-dehydroalanine residues, the H-bond in their complexes with water are stronger than for standard alanine.

https://doi.org/10.1080/00268976.2013.847979