title: UV raman examination of alpha-helical peptide water hydrogen bonding.
abstract: UV resonance Raman spectra (UVRS) of an alpha-helical, 21 residue, mainly Ala peptide (AP) in the dehydrated solid state were compared to those in aqueous solution at different temperatures. The UVRS amide band frequencies of a dehydrated solid alpha-helix peptide show frequency shifts compared to those in aqueous solution due to the loss of amide backbone hydrogen bonding to water; the amide II and amide III bands of the solid alpha-helix downshift, while the amide I band upshifts. The shifts are identical in direction but smaller than those that occur for alpha-helices in aqueous solution as the temperature increases; water hydrogen bonding strengths decrease as the temperature increases. The UV Raman amide band frequency shifts can be used to monitor alpha-helix hydrogen bonding.
authors.affiliation: Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260.
authors.forename: Konstantin V
authors.initials: KV
authors.lastname: Pimenov
authors.forename: Sergei V
authors.initials: SV
authors.lastname: Bykov
authors.forename: Aleksandr V
authors.initials: AV
authors.lastname: Mikhonin
authors.forename: Sanford A
authors.initials: SA
authors.lastname: Asher
mesh_terms: D003080:Cold Temperature; D006358:Hot Temperature; D006860:Hydrogen Bonding; D007700:Kinetics; D010455:Peptides / Q000737:chemistry*; D011099:Polyglutamic Acid / Q000737:chemistry; D011107:Polylysine / Q000737:chemistry; D017433:Protein Structure, Secondary; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D013059:Spectrum Analysis, Raman / Q000379:methods; D014867:Water / Q000737:chemistry*
chemical_list: D010455:Peptides; D014867:Water; D011107:Polylysine; C019529:polyalanine; D011099:Polyglutamic Acid