Amino acid sequence of a Crotalus atrox venom metalloproteinase which cleaves type IV collagen and gelatin.
The hemorrhagic toxin Ht-d from venom of the Western diamondback rattlesnake is a metalloproteinase with a molecular weight of 23,234. Peptides were obtained from enzymatic and chemical digestions, separated by reverse-phase chromatography, and sequenced in a gas-phase sequenator. The sequence showed a putative zinc binding site similar to that of thermolysin and other metalloproteinases but no overall significant similarity to the sequences of other metalloproteinases and may represent a new subfamily of metalloproteinases. Ht-d was shown to degrade type IV collagen and gelatin types I, III, and V but not interstitial collagens. The digestion of type IV collagen and other basement membrane proteins may allow this proteinase to disrupt capillary membranes causing hemorrhage in surrounding tissues.
Shannon
J D
JD
Department of Microbiology, School of Medicine, University of Virginia, Charlottesville 22908.
Baramova
E N
EN
Bjarnason
J B
JB
Fox
J W
JW
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis*; D000818:Animals; D001665:Binding Sites; D002851:Chromatography, High Pressure Liquid; D003094:Collagen / Q000378:metabolism*; D003435:Crotalid Venoms / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D005780:Gelatin / Q000378:metabolism*; D006868:Hydrolysis; D008666:Metalloendopeptidases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D008969:Molecular Sequence Data; D051381:Rats; D013379:Substrate Specificity; D015032:Zinc / Q000378:metabolism
D000596:Amino Acids; D003435:Crotalid Venoms; D005780:Gelatin; D003094:Collagen; D008666:Metalloendopeptidases; C044577:atrolysin A; D015032:Zinc