title: [Secondary structure and assignment of signals in two-dimensional 1H-NMR spectra of the Buthus eupeus neurotoxin I5A].
abstract: The complete assignment of the 500 MHz 1H nuclear magnetic resonance spectrum of the insectotoxin I5A isolated from Buthus eupeus scorpion venom is performed by two-dimensional spectroscopy. The analysis of nuclear Overhauser effects for the protons of neighbouring residues in the amino acid sequence established the secondary structure of the molecule: alpha-helical part from Asn11 to Gly21 and anti-parallel beta-structure from asn23 to Asn34 with the beta-turn Phe27-Gly28-Pro29-Gln30. Three X-Pro peptide bonds have trans configuration. The primary structure of isotoxin was corrected by NMR and confirmed by sequencing.
mesh_terms: D000595:Amino Acid Sequence; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008958:Models, Molecular; D009498:Neurotoxins; D010455:Peptides; D011487:Protein Conformation; D012604:Scorpion Venoms
chemical_list: D009498:Neurotoxins; D010455:Peptides; D012604:Scorpion Venoms
vernacular_title: Vtorichnaia struktura i otnesenie signalov v dvumernykh spektrakh 1H-IaMR insektotoksina I5A Buthus eupeus.