Cloning and nucleotide sequence of a cDNA encoding ammodytoxin A, the most toxic phospholipase A2 from the venom of long-nosed viper (Vipera ammodytes).
A venom gland cDNA library was constructed in pUC9 and screened with a mixed oligonucleotide probe deduced from the unique Glu-4 to Ile-9 region of ammodytoxins. Twenty-one strongly positive clones were found by hybridization of about 5000 bacterial colonies, nine of them with the inserts encoding ammodytoxin A. The cDNA for ammodytoxin A encodes a 122 amino acid residue mature protein, preceded by a 16 residue signal peptide. Its complete nucleotide sequence shows 99% similarity to those of ammodytoxins B and C.
Amino Acid Sequence↗