0 avis
Ligands as a Tool to Tune the Toxicity of Cu on Bacteria: from Boosting to Silencing
Archive ouverte
Edité par CCSD ; WORLD SCIENTIFIC -
International audience. Copper is an essential micronutrient for most living beings includingbacteria. This is mainly due to essential roles of catalytic Cu-centersin enzymes. However, an excess of Cu is toxic and thereby used overcenturies as a powerful antimicrobial agent. Bacteria developedseveral systems to detect Cu and protect themselves from highintracellular Cu concentration, namely via Cu-extrusion and/or Custorage.Several Cu-detoxification systems have been described andnew ones are still being discovered. Progress has also been made inunderstanding the molecular mechanism of Cu-toxicity byidentifying target macromolecules. Nevertheless, the importance ofeach mechanism is bacteria- and environment-dependent paving theway for new findings.The chemical reactivity of Cu can be modulated by its coordinationenvironment in a complex with a ligand (L) and this opens largeopportunities to tune the Cu-ligand complexes (Cu-L) via liganddesign. For instance, boosting the toxicity of Cu ions toward bacteriawas promoted by several small organic ligands. These ligands canmake Cu-L complexes with different properties in terms ofcoordinating atoms (S, N, O), Cu to L stoichiometry, liganddenticity, thermodynamic stability, kinetic inertia and redoxpotential. However, one common feature shared by Cu-L complexeswhich efficiently boost Cu-toxicity is the ability of Cu-L to cross thetwo bacterial membranes and to release the Cu in the cytosol. If thisproperty is required to improve bacteria killing is not clear yet, butconsidering the ever-growing resistance of bacteria, it would beinteresting in the future to try to boost Cu-toxicity via unprecedentedmechanisms.
Consulter en ligne
Suggestions
Du même auteur
