Am. Cancel et al., LIGNIN AND VERATRYL ALCOHOL ARE NOT INDUCERS OF THE LIGNINOLYTIC SYSTEM OF PHANEROCHAETE-CHRYSOSPORIUM, Applied and environmental microbiology, 59(9), 1993, pp. 2909-2913
Phanerochaete chrysosporium is a white rot fungus which secretes a fam
ily of lignin-degrading enzymes under nutrient limitation. In this wor
k, we investigated the roles of veratryl alcohol and lignin in the lig
ninolytic system of P. chrysosporium BKM-F-1767 cultures grown under n
itrogen-limited conditions. Cultures supplemented with 0.4 to 2 mM ver
atryl alcohol showed increased lignin peroxidase activity. Addition of
veratryl alcohol had no effect on Mn-dependent peroxidase activity an
d inhibited glyoxal oxidase activity. Azure-casein analysis of acidic
proteases in the extracellular fluid showed that protease activity dec
reased during the early stages of secondary metabolism while lignin pe
roxidase activity was at its peak, suggesting that proteolysis was not
involved in the regulation of lignin peroxidase activity during early
secondary metabolism. In cultures supplemented with lignin or veratry
l alcohol, no induction of mRNA coding for lignin peroxidase H2 or H8
was observed. Veratryl alcohol protected lignin peroxidase isozymes H2
and H8 from inactivation by H2O2. We conclude that veratryl alcohol a
cts as a stabilizer of lignin peroxidase activity and not as an induce
r of lignin peroxidase synthesis.