Infrared evidence of a beta-hairpin peptide structure in solution.
The IR spectrum of an 16-amino acid peptide corresponding, according to NMR studies, to a beta-hairpin has been analysed. Two characteristic features distinguish its spectrum from that of an antiparallel beta-sheet: the low-frequency band that in a beta-sheet structure is located at approximately 1632 cm-1 appears here at approximately 1620 cm-1, and the high-frequency component does not undergo the isotopic shift typical of beta-sheet from 1690 to 1675 cm-1 when transferred to D2O. The infrared characteristics associated with beta-hairpins have been described so far in two proteins, in one of which, whose three-dimensional structure is known from X-ray diffraction, a beta-hairpin has actually been detected.
Arrondo
J L
JL
Departamento de Bioquímica, Universidad del País Vasco, Bilbao Spain. GBPROARJ@LG.EHU.ES
Blanco
F J
FJ
Serrano
L
L
Goñi
F M
FM
D001426:Bacterial Proteins / Q000737:chemistry*; D017666:Deuterium Oxide; D009682:Magnetic Resonance Spectroscopy; D010446:Peptide Fragments / Q000737:chemistry; D010455:Peptides / Q000737:chemistry*; D017433:Protein Structure, Secondary; D013055:Spectrophotometry, Infrared / Q000379:methods; D013291:Streptococcus; D013816:Thermodynamics; D014961:X-Ray Diffraction
D001426:Bacterial Proteins; C034284:IgG Fc-binding protein, Streptococcus; D010446:Peptide Fragments; D010455:Peptides; D017666:Deuterium Oxide