Copper oxygenase model systems

The classical endo-exo deconstruction model of pure cellulose is undergoing revision in light of the recent discovery of a family of copper-dependent polysaccharide mono-oxygenases from the GH61 family (Table 4.1) (Harris et al., 2010 Quinlan et al., 2011). These enzymes represent a novel mechanism to deconstruct cellulose in that they cleave cellulose oxidatively, unlike traditional acid/base catalyzed enzyme systems. Family GH61 enzymes can also provide powerful synergistic benefits to cocktails of traditional GH5, GH6, and GH7 enzyme mixtures (Harris et al., 2010). 

Formation of metal-oxo species first became realistic in model studies on heme oxygenases (shunt path), and it has also become popular in nonheme systems. As for the metal-jd-peroxo species, the distinctive example of model study has appeared in the copper enzymes. The type 7 peroxo species has been proposed first based on models for dicopper oxy-hemocyanin [19, 20] before demonstration of the same oxygen bonding in enzyme [13]. The type 7 x-peroxo structure has been applied to diiron species in sMMO [14] in addition to 6 [21]. (see Chapter 8)... 

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