A comparative study of the enzymatic characteristics of the primordium-specific laccase Lacc12 and the constitutive laccase Lacc6 showed that the ABTS oxidation activity of Lacc12 was 40% that of Lacc6. Moreover, the optimal pH and temperature for Lacc12 activity were 0.5 pH units and 5oC higher than those for Lacc6 (Fig. 5B and 5C). These findings may reflect the physiological conditions during the primordiation stage. In L. edodes, laccase activity in the sawdust substrate decreased dramatically at the primordial stage, along with a sharp increase in cellulase activity [35]. These findings suggest that laccase activity is necessary for the vegetative growth of mycelia in the sawdust substrate and potentially for lignin degradation. Degradation of lignin or production of lignin-derived compounds may induce primordiation. Upon primordiation, laccase activity in the substrate is no longer required. Instead, activity within primordia is necessary for the completion of primordiation, with cellulases of the mycelia beneath the primordia digesting the cellulosic substrate to provide a source of carbon and energy. Volvariella volvacea shows a high level of expression of a laccase gene, lac1, as well as high laccase activity, particularly during the primordial stage [36]. Taken together, these findings indicate that different laccases function at various stages of development as well as in lignin degradation.