Nucleotide-Sequence Encoding the Snake-Venom Fibrinolytic Enzyme Atroxase Obtained from a Crotalus atrox Venom Gland cDNA Library

Atroxase, isolated from the venom of Crotalus atrox (western diamondback rattlesnake), is a nonhemorrhagic protease which has fibrinolytic activity in vivo. The primary structure of atroxase was deduced from the cDNA encoding the atroxase protein. The venom glands of Crotalus atrox were used to prepare a cDNA library. Degenerate oligonucleotides mere synthesized based on the partial amino acid sequence of atroxase and were used as primers in the polymerase chain reaction to amplify overlapping cDNA fragments from the C. atrox cDNA library. The resulting cDNA fragments were subcloned, sequenced, and translated. The final nucleotide sequence shows high homology to previously described primary structures of nonhemorrhagic fibrinolytic proteases isolated from snake venom.