1H-NMR signal assignments and secondary structure analysis of martentoxin.

Authors :: WANG, Y.-H.
CAO, Z.-Y.
HE, W.-Y.
YAN, X.-Z.
LIU, X.
LIU, H.-Y.
LIANG, X.-T.
YU, D.-Q.
Source :: Journal of Asian Natural Products Research. Sep2006, Vol. 8 Issue 6, p511-518. 8p.
Publication Year :: 2006
Abstract: Martentoxin is a peptide of 37 amino acid residues purified from the venom of the Chinese scorpion Buthus martensi Karch, which has been demonstrated to be an inhibitor of voltage-dependent sodium channel and voltage-dependent delayed rectifier potassium channel. To elucidate the molecular mechanism of this interaction, the structure of martentoxin was studied by 2D-NMR. The secondary structure of martentoxin consists of a triple-stranded β-sheet connected to a α-helical structure. This helix encompasses 10 residues from Ser11 to Lys20. The three strands of β-sheet probably comprise residues Gly2-Asp5, Q27-N30 and Glu33-Cys36, Cys30-Asn33 with a type I′β turn centered on Asn31-Asn32. The results indicate that martentoxin possesses the conserved β α β β structure of all the potassium channel toxins. [ABSTRACT FROM AUTHOR]