EFFECT OF NUTRIENT NITROGEN AND MANGANESE ON MANGANESE PEROXIDASE ANDLACCASE PRODUCTION BY LENTINULA (LENTINUS) EDODES

Lentinula (Lentinus) edodes, strain L54, produces manganese-dependent peroxidase (MnP) and laccase, but not lignin peroxidase, when grown on a defined medium with glucose as sole carbon source. MnP production i s suppressed by nitrogen whereas highest levels of laccase were observ ed when the fungus was grown under high nitrogen (26 mM) conditions. B oth the titre and time of appearance of MnP were affected by the conce ntration of Mn in the culture medium with highest enzyme levels record ed in cultures supplemented with 1.1 ppm Mn. Purified MnP from L. edod es L54 has an apparent M(r) of 59 000 and a pI of 5.6, and differs in several respects from a MnP isolated from L. edodes grown on a commerc ial wood substrate.