EXTRACELLULAR PHENOLOXIDASE AND PEROXIDASE ENZYME-PRODUCTION DURING INTERSPECIFIC FUNGAL INTERACTIONS

Extracellular phenoloxidase enzymes have been implicated in the offens ive/defensive strategies employed by fungi during interactions. To det ermine whether these enzymes are involved during Basidiomycete confron tations, a number of pairings between two brown-rot Basidiomycetes (Se rpula lacrymans and Coniophora puteana) and several Deuteromycetes (Tr ichoderma spp. and Scytalidium FY) were performed. Laccase production was observed in pure cultures of C. puteana and Scytalidium FY, and in the interactions involving these two species. Laccase was also detect ed in the interactions involving S. lacrymans and all three Trichoderm a isolates, although not in the respective pure cultures. Tyrosinase r elease was observed most frequently in interactions involving T. harzi anum SIWT 25, although all other species also released tyrosinase unde r certain conditions, and peroxidase release was detected during all i nterspecific interactions. One exception involved T. viride SIWT 110 a s this fungus did not produce tyrosinase under the experimental parame ters utilized, and peroxidase release was inhibited during self-pairin gs and pairings involving the two other Trichoderma isolates. Extracel lular laccase and tyrosinase production was much less on a low nutrien t medium, although peroxidase production was not affected as strongly. (C) 1997 Elsevier Science Limited.