Michaut, L., Fehlbaum, P., Moniatte, M., van Dorsselaer, A., Reichhart, J.M., Bulet, P. (1996). Determination of the disulfide array of the first inducible antifungal peptide from insects: drosomycin from Drosophila melanogaster.  FEBS Lett. 395(1): 6--10.

FBrf0090699

Research paper

Drosomycin is a 44-residue antifungal peptide with four intramolecular disulfide bridges which have been isolated from immune-challenged Drosophila. To produce adequate amounts of this peptide for 3D-structure analysis, studies on the mode of action and activity spectrum, we expressed a synthetic cDNA in Saccharomyces cerevisiae. For this purpose, we used the mating factor alpha gene and concomitantly overexpressed the KEX2 gene to increase the yield of fully processed drosomycin. Using a combination of Edman degradation and mass spectrometry, we show that drosomycin shares the same array of intramolecular disulfide bridges than plant defensins, in addition to their sequence similarities.