An alternative to the reaction investigated in the previous subsection is the abstraction of a hydrogen from the histidine brace by the [CuO] + moiety in 1 (i.e., reaction II in Fig. ). Indeed, we recently investigated this for LsAA9 as the first step of the oxidative self-damage reaction. We compare the reaction profiles (barrier and reaction energy) of reaction II for TaAA9 and LsAA9 in Fig. (all calculated energies associated with reaction II are provided in Table ). As can be seen from Fig. , LsAA9 and TaAA9 overall have the same energy profile for the H-abstraction from the active site histidine (His1). The reaction barrier differs only by 5 kJ/mol (1 kJ/mol for TPSS) and the reaction energy differs by less than 3 kJ/mol for both functionals. Thus, the oxidative damage can proceed through this pathway, independent of the LPMO.