[1][2] AA9 is known to be a copper dependent, oxidative enzyme able to cleave crystalline cellulose.
[3] Activity greatly depends on the presence of a divalent copper ion and a reductant such as gallate or ascorbate.
The oxidative action of AA9 can work on either the reducing or the non-reducing end of glucose moieties.
[citation needed] Although AA9 enzymes can be found in a large spectrum of biomass degrading fungi, research into this family is relatively new.
[4] This classification is available on the CAZy web site,[5][6] and also discussed at CAZypedia, an online encyclopedia of carbohydrate active enzymes.