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Title: Calcium‐Ion Binding Mediates the Reversible Interconversion of Cis and Trans Peroxido Dicopper Cores
Abstract

Coupled dinuclear copper oxygen cores (Cu2O2) featured in type III copper proteins (hemocyanin, tyrosinase, catechol oxidase) are vital for O2transport and substrate oxidation in many organisms.μ‐1,2‐cisperoxido dicopper cores (CP) have been proposed as key structures in the early stages of O2binding in these proteins; their reversible isomerization to other Cu2O2cores are directly relevant to enzyme function. Despite the relevance of such species to type III copper proteins and the broader interest in the properties and reactivity of bimetallicCPcores in biological and synthetic systems, the properties and reactivity ofCPCu2O2species remain largely unexplored. Herein, we report the reversible interconversion ofμ‐1,2‐transperoxido (TP) andCPdicopper cores. CaIImediates this process by reversible binding at the Cu2O2core, highlighting the unique capability for metal‐ion binding events to stabilize novel reactive fragments and control O2activation in biomimetic systems.

 
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PAR ID:
10281679
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie
Volume:
133
Issue:
36
ISSN:
0044-8249
Page Range / eLocation ID:
p. 19989-19995
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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    Coupled dinuclear copper oxygen cores (Cu2O2) featured in type III copper proteins (hemocyanin, tyrosinase, catechol oxidase) are vital for O2transport and substrate oxidation in many organisms.μ‐1,2‐cisperoxido dicopper cores (CP) have been proposed as key structures in the early stages of O2binding in these proteins; their reversible isomerization to other Cu2O2cores are directly relevant to enzyme function. Despite the relevance of such species to type III copper proteins and the broader interest in the properties and reactivity of bimetallicCPcores in biological and synthetic systems, the properties and reactivity ofCPCu2O2species remain largely unexplored. Herein, we report the reversible interconversion ofμ‐1,2‐transperoxido (TP) andCPdicopper cores. CaIImediates this process by reversible binding at the Cu2O2core, highlighting the unique capability for metal‐ion binding events to stabilize novel reactive fragments and control O2activation in biomimetic systems.

     
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