Evidence for H-bonding interactions to the μ-η:η-peroxide of oxy-tyrosinase that activate its coupled binuclear copper site.

The factors that control the diverse reactivity of the μ-η:η-peroxo dicopper(II) oxy-intermediates in the coupled binuclear copper proteins remain elusive. Here, spectroscopic and computational methods reveal H-bonding interactions between active-site waters and the μ-η:η-peroxide of oxy-tyrosinase, and define their effects on the Cu(II)O electronic structure and O activation.