Two kinins isolated from an extract of the venom reservoirs of the solitary wasp Megascolia flavifrons.

From an extract of the venom reservoirs of the wasp Megascolia flavifrons two kinins have been isolated. The sequences of amino acids are: Arg-Pro-Pro-Gly-Phe-Thr-Pro-Phe-Arg (Thr6-bradykinin) and Arg-Pro-Pro-Gly-Phe-Thr-Pro-Phe-Arg-Lys-Ala (Thr6-bradykinin-Lys-Ala). The bradykinin-like effects of the venom on a number of vertebrate smooth muscle preparations can be explained by the actions of these kinins.