Distribution of Polyphenol Oxidase in Organelles of Hyphae of the Wood-Deteriorating Fungus, Coriolus Versicolor

Coriolus versicolor, a white-rot Basidiomycete, secretes cellulolytic and ligninolytic enzymes (Higuchi, 1953; Rosenberg, 1979; Harvey et al., 1987) as well as polyphenol oxidase (Taylor et al., 1987; Moore et al., 1989). Whereas the former degrade certain wood polymers (Higuchi, 1985), the latter can convert o-diphenols to o-diquinones (Fric, 1976) and oligomerize syringic acid (Liu et al., 1981), a lignin derivative. In this connection, certain phenolic compounds can serve as disease-resistance factors possibly regulating the proliferation of wood-decay fungi within host tissues (Shigo, 1984; Dashek et al., 1990). Because ligno-cellulolytic enzymes are of commercial value to the paper-pulp industry (Zadrazil and Reiniger, 1988) and the agricultural community (Van der Meer et al., 1987), an inexpensive and “readily-available” supply of these enzymes is highly desirable. As C. versicolor can be “batch-cultured”, over-production and enhanced secretion of these enzymes are feasible (Fahraeus and Reinhammer, 1967). While over-production could possibly be achieved by substrate induction and/or recombinant DNA technologies (Maniatis et al., 1982), secretion might be enhanced by controlling cellular energy gradients and/or possible glycosylation of PPO.