Trapping tyrosinase key active intermediate under turnover.

This paper shows for the first time that the spectral features of the ternary complex of tyrosinase/O2/phenol, trapped at low temperature using the very slow substrate 3,5-difluorophenol, are those of a mu-eta2:eta2-peroxidodicopper(II) species, and that this remains the only enzyme species under turnover and substrate saturation conditions.