Induction of L-phenylalanine ammonia-lyase and suppression of veratryl alcohol biosynthesis by exogenously added L-phenylalanine in a white-rot fungus phanerochaete chrysosporium
The effects of exogenously added L-phenylalanine (L-Phe) on the activities of L-phenylalanine ammonia-lyase (PAL) and 3, 4-dimethoxybenzyl alcohol (veratryl alcohol, VA) biosynthesis in ligninolytic cultures of Phanerochaete chrysosporium were investigated. Increasing PAL activity was detected in low nitrogen (LN) culture but not in high nitrogen (HN) culture. The addition of L-Phe into the LN culture caused a 25-fold increase in enzyme activity, which clearly shows that L-Phe, a substrate of the enzyme, served as an inducer of PAL. The increase in activity of PAL triggered by nitrogen starvation was correlated with biosynthesis of VA. However, PAL induced by the added L-Phe did not promote VA biosynthesis but suppressed the biosynthesis probably due to NH(4)(+) released from L-Phe.
Hattori
T
Wood Research Institute, Kyoto University, Uji, Kyoto, Japan.
Nishiyama
A
Shimada
M