Magainin-2

Antimicrobial peptides are a diverse group of molecules possessing a broad spectrum of antibiotic properties that are being considered as novel therapeutic agents.  Many of these agents are membrane active, killing bacteria by membrane disruption, but an increasing number of  antimicrobial peptides have been shown to enter cells and target intracellular processes fundamental to bacterial existence.   

Di Somma et al investigated the mechanism of action of magainin-2, an antimicrobial peptide isolated from the African clawed frog Xenopus laevis, by functional proteomic approaches.  Proteins belonging to E. coli macromolecular membrane complexes were identified as putative interactors, including BamA, the membrane protein belonging to the BAM complex responsible for the folding and insertion of nascent β-barrel outer membrane proteins in the outer membrane.  Molecular modelling, in vitro fluorescence binding and light scattering experiments confirmed the formation of a stable Mag-2/BamA complex and a high affinity of the peptide for BamA.  The absence of BamA in humans and its involvement in crucial biological events in bacterial life suggest BamA as a potential novel target for the design of new antibiotics.