Biosynthesis of Melittin, a Toxic Peptide from Bee Venom.

From the venom glands of honey bees fed with different radioactive amino acids, labelled promelittin could be isolated. Extensive analysis of this precursor peptide has led to the conclusion that it contains the entire sequence of melittin, including the C-terminal glutamic acid diamide. At the amino end, promelittin was found to be heterogeneous. As compared to melittin, the main species contains eight additional amino acids. Other species of different chain length are present in varying amounts. The structure of the main component can be formulated as Glu-Pro-Glu-Pro-Asp-Pro-Glu-Ala-melittin(1–26). The methodology used for determining the sequence of radioactive peptides is discussed. [ABSTRACT FROM AUTHOR]