Mono and two-dimensional 500-MHz characterization of synthetic bombesin and related peptides in DMSO and DMSO-water.
The proton nmr characterization of bombesin (BBS) and of two peptide fragments corresponding to the (1-6) and (6-14) sequences has been carried out at 500 MHz in dimethyl sulfoxide (DMSO-d6) using two-dimensional (2D) homo and 1H-13C heterocorrelated techniques. All resonances in the nmr spectra have been assigned and several coupling constants have been measured. The backbone J alpha CH-NH coupling constants are quite similar and around 7.8-8.2 Hz, pointing to an unfolded structure in DMSO-d6. The possibility of secondary structures in highly viscous mixtures of DMSO-d6-water was investigated. The existence of sequential nuclear Overhauser enhancement (NOE) effects in the C-terminal nonapeptide section may indicate a preferential site for secondary structuring.
Di Bello
C
C
Gozzini
L
L
Tonellato
M
M
Corradini
M G
MG
D'Auria
G
G
Paolillo
L
L
Trivellone
E
E
D001839:Bombesin / Q000138:chemical synthesis; D004121:Dimethyl Sulfoxide; D009682:Magnetic Resonance Spectroscopy; D009842:Oligopeptides / Q000138:chemical synthesis; D011487:Protein Conformation; D014867:Water
D009842:Oligopeptides; D014867:Water; D001839:Bombesin; D004121:Dimethyl Sulfoxide