Isolation, purification and partial characterization of laccase from ustilago maydis

Huitlacoche is a fungus that has been consumed in Mexico since prehispanic times. This Aztec name is given to the galls or tumors that form in corn cobs by the fungus scientifically known as Ustilago maydis. When infection takes place, a great mass of mycelium is formed in different zones in the corn plant. In the end, a great mass of black spores replaces the mycelium, and it is at this stage that the product is consumed as food (Valverde et al., 1995). Laccase (p-diphenol oxygen oxidoreductase, E. C. 1.10.3.2) catalyzes the oxidation of p-hydroxyphenols. Its activity depends on copper, oxidizes o- and p-dihydroxyphenols and compounds such as p-phenylendiamine and syringaldazine to color final products. Laccases differ from p-diphenol oxidases in their ability to hydroxylate monophenols (Walker, 1995; Palmieri et al., 1997). The objective of this work was to isolate, purify and partially characterize (biochemically and physico-chemically) the laccase from U. maydis.