EXTRACELLULAR PEROXIDASE AND PHENOLOXIDASE ACTIVITY OF THERMOMONOSPORA-MESOPHILA

Growth of Thermomonospora mesophila on minimal medium (MM) containing dimeric and trimeric lignin-related compounds was substantially less t han growth on MM plus glucose. Peroxidase activity using L-DOPA as sub strate was greatest in glucose-grown cells during the decline phase of growth, and for the dimer and trimer during exponential growth. Activ ity for phenoloxidase using L-DOPA as substrate and peroxidase using o -dianisidineas substrate occurred at similar growth phases. Relatively high levels of phenoloxidase activity with o-dianisidine as substrate were observed during exponential growth on glucose which continued in to the decline phase, whereas with the dimer and trimer the greatest a ctivities were evident during the exponential growth. The levels of en zyme activity varied considerably between the assays.