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Hydrogen bonding in peptide secondary structures
Author(s) -
Varga Zoltán,
Kovács Attila
Publication year - 2005
Publication title -
international journal of quantum chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.484
H-Index - 105
eISSN - 1097-461X
pISSN - 0020-7608
DOI - 10.1002/qua.20706
Subject(s) - hydrogen bond , chemistry , amide , conformational isomerism , crystallography , moiety , polarizability , interaction energy , helix (gastropod) , alanine , hydrogen , stereochemistry , molecule , organic chemistry , amino acid , ecology , biochemistry , snail , biology
Hydrogen bonding interactions in various peptide secondary structures (β‐sheet, 2 7 ‐ribbon, 3 10 ‐helix, α‐helix, π‐helix, β‐turn II, and γ‐turn) have been investigated in small oligopeptides by quantum chemical calculations at the B3LYP/6‐31G** level. Besides the primary O…HN interactions, the optimized structures revealed the importance of N…HN hydrogen bonding in several structures. The effect of substitution on the energy and structural properties was investigated comparing the properties of glycine, alanine, valine, and serine. The aliphatic substituents generally weaken the hydrogen bonds, the strongest effects being observed in crowded valine conformers. Additional hydrogen bonding interactions introduced by the OH group of serine can both strengthen (by polarizing the amide moiety through N…H interaction) and weaken (constraining the CO oxygen by O…HO interaction) the backbone hydrogen bonds. The effect of water as a polarizable medium on the energy properties was assessed by the COSMO model. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005