Crystal structure of the platelet activator convulxin, a disulfide-linked alpha4beta4 cyclic tetramer from the venom of Crotalus durissus terrificus

Biochem Biophys Res Commun. 2003 Oct 17;310(2):478-82. doi: 10.1016/j.bbrc.2003.09.032.

Abstract

Convulxin (CVX), a C-type lectin, isolated from the venom of the South American rattlesnake Crotalus durissus terrificus, causes cardiovascular and respiratory disturbances and is a potent platelet activator which binds to platelet glycoprotein GPVI. The structure of CVX has been solved at 2.4A resolution to a crystallographic residual of 18.6% (R(free)=26.4%). CVX is a disulfide linked heterodimer consisting of homologous alpha and beta chains. The heterodimers are additionally linked by disulfide bridges to form cyclic alpha(4)beta(4)heterotetramers. These domains exhibit significant homology to the carbohydrate-binding domains of C-type lectins, to the factor IX-binding protein (IX-bp), and to flavocetin-A (Fl-A) but sequence and structural differences are observed in both the domains in the putative Ca(2+)and carbohydrate binding regions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Binding Sites
  • Calcium / metabolism
  • Crotalid Venoms / chemistry*
  • Crotalid Venoms / metabolism
  • Crotalus*
  • Crystallography, X-Ray
  • Disulfides / chemistry
  • Lectins, C-Type / chemistry*
  • Lectins, C-Type / metabolism
  • Models, Molecular*
  • Molecular Sequence Data
  • Protein Structure, Quaternary
  • Protein Subunits
  • Sequence Alignment

Substances

  • Crotalid Venoms
  • Disulfides
  • Lectins, C-Type
  • Protein Subunits
  • convulxin
  • Calcium

Associated data

  • PDB/1UMR