Polysaccharide monoxygenases: giving a boost to biofuel production.

In this issue of Structure, Li et al. present high resolution crystal structures of two fungal polysaccharide monoxygenases. Unexpectedly, they observe oxygen species bound at the active sites that inform on the chemistry that can be supported by these enzymes. Additionally, the organization of aromatic amino acids and glycosylation on the carbohydrate binding surfaces suggests that regiospecificity and cellulose orientation can be predicted.