Dalvit C, Widmer H, Bovermann G, Breckenridge R, Metternich R
Preclinical Research, Sandoz Pharma AG.
Eur J Biochem. 1991 Dec 5;202(2):315-21. doi: 10.1111/j.1432-1033.1991.tb16378.x.
Two-dimensional 1H-NMR methods have been used to obtain complete proton resonance assignments for the 49-residue protein echistatin from the viper Echis carinatus. The protein in solution contains only a small amount of regular secondary structure with four very short beta-strands. These beta-strands form two short segments of antiparallel beta-sheet, as evidenced by the observed cross-strand NOE. The first two strands are connected with a tight reverse turn, whereas the remaining two strands are linked together by an 11-residue loop forming a so-called hairpin. The tripeptide unit Arg-Gly-Asp, responsible for the binding of echistatin to the fibrinogen receptor glycoprotein GPIIb/IIIa, is located at the tip of this very hydrophilic loop.
