Nitrogen ions change transfer mechanism

Unlike ATXl, where the chemistry of copper transfer is well understood, the mechanism of copper transfer from CCS to SODl remains unclear. For example, a dramatic change in metal ion coordination chemistry must accompany the copper transfer process in this case. Copper is bound to CCS in the reduced Cu(I) form via sulfhydral ligands, while in SODl, copper is oxidized to the cupric Cu(II) state and is coordinated in an all-nitrogen environment to four histidines. The driving force for this large change in coordination chemistry is still poorly understood, but may involve an external oxidant, such as the superoxide substrate itself... 

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