Unveiling Copper Adaptation Mechanisms in Bacteria: Insights from Bufferin-Copper Complexes via X-ray Absorption Spectroscopy

A necessary metal that is toxic in excess, copper induces adaptive responses in bacteria. Bacterial resistance or tolerance to this agent has thus become a problem in healthcare and agriculture. We identified a new mechanism for copper adaptation based on post-translationally modified peptides called ‘bufferins’ that enhance bacterial growth in the presence of excess copper, through the formation of complexes with copper. Our objective is to exploit X-ray Absorption Spectroscopy to investigate the copper binding site of bufferins in order to gain insight into what is likely to become a new path toward bacterial resistance.