title: Crotalocytin: recognition and purification of a timber rattlesnake platelet aggregating protein.
abstract: After being envenomated by the timber rattlesnake, a patient was found to have a platelet count of 5000 per microliter, prothrombin time and activated partial thromboplastin time both greater than 150 sec, plasma fibrinogen 0 mg/dl, and fibrinogen split products 2560 microgram/ml. However, this patient did not appear to have acute disseminated intravascular coagulation since coagulation factors II-XII were normal. We postulated that this venom contained, in addition to a fibrinogen clotting enzyme, a platelet activating protein, Crotalocytin. Crotalocytin was purified from crude timber rattlesnake venom by Sephadex G-100 gel-filtration, low ionic strength precipitation, and DEAE-A50 Sephadex chromatography. By sodium dodecyl sulfate gel electrophoresis and gel-filtration Crotalocytin was a single chain polypeptide, molecular weight 55,000. Thrombocytopenia after timber rattlesnake bite appeared to be due to a protein that directly activated platelets. Timber rattlesnake bite mimicked the clinical presentation of disseminated intravascular coagulation.
mesh_terms: D000596:Amino Acids; D000818:Animals; D011232:Chemical Precipitation; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D003435:Crotalid Venoms / Q000494:pharmacology*; D004591:Electrophoresis, Polyacrylamide Gel; D007106:Immune Sera / Q000494:pharmacology; D008297:Male; D009994:Osmolar Concentration; D010974:Platelet Aggregation; D011506:Proteins / Q000302:isolation & purification*; D012911:Snakes
chemical_list: D000596:Amino Acids; D003435:Crotalid Venoms; D007106:Immune Sera; D011506:Proteins; C027697:crotalocytin