Metal Ions And Peptides – A Bioinorganic Symphony For Antimicrobial Action

Unraveling how metal ions influence antimicrobial peptides (AMPs), our work offers new insights that may contribute to the field of beautiful, fundamental bioinorganic chemistry. We show that coordination of Zn(II) and Cu(II) ions to AMPs can significantly enhance their antimicrobial activity by modulating peptide structure, morphology, and local charge.[1] Our project revealed, for the first time, that Zn(II) binding to amyloidogenic peptides such as pramlintide, amylin analogs, and shepherin induces the formation of amyloid fibrils, which appear to underlie their potent antifungal effects. This “coordination-induced fibrillization” proceeds via a clear trajectory: distal metal binding → structural rearrangement → fibril formation → antifungal activity. This insight introduces a new perspective on the role of functional amyloids in antimicrobial action.[2] In the case of piscidins or semenogelins, we show that their antimicrobial effect arises from the locally cationic character of their metal complexes, which promotes interactions with negatively charged microbial membranes.[3,4] Together, these findings deepen our understanding of metal-peptide interactions and may offer a foundation for the rational design of metal-based antimicrobial strategies. By bridging molecular coordination chemistry with mechanisms of microbial resistance, we hope to take one tiny small step toward addressing a major medical challenge.