Abstract: | Orientotoxin I, a neurotoxin of presynaptic effect having a lysophospholipase activity, and orientotoxin II, a highly toxic phospholipase A2, were isolated from the hornet Vespa orientalis venom, and their primary structures were determined. Despite their different functional activity, orientotoxin I and II proved to be structural homologues, differing significantly in the amino acid sequence from well-known toxic phospholipase from other sources. |