Phytochrome enhances nitrate reductase activity in the lichenEvernia prunastri

摘要

The lichenEvernia prunastrishortly after collection shows low nitrate reductase activity. The enzyme is induced by nitrate in the dark and this effect is enhanced by red light, the action of which is reversed by far-red light. Nitrate reductase is located in both symbionts, but mycobiont cells are responsible for the increase of enzyme activity in whole thalli floated on nitrate in the dark. When this increase is achieved in the light, it can be related to the Pfrcontent of the photobiont cells, whereas changes in the activity of the fungal enzyme are negligible.