Full text loading...
Abstract
Protoplasts of Claviceps purpurea (ATCC 20102) were prepared in 0·8 m-sucrose containing 10 mm-CaCl2 and 10 mm-MgCl2. Protoplasts could revert to the filamentous state but not after treatment with water. Most of the protoplasts (about 80%) were highly vacuolated and these were separated from the non-vacuolated protoplasts and cell debris on the basis of their low density. Only the vacuolated protoplasts were able to synthesize ergotamine and ergocryptine de novo. Protoplasts were about 50% less active than the control mycelium. The control mycelium was more active in the uptake of labelled precursors than both protoplasts and freshly harvested mycelium. In the amino acid pool of protoplasts, alanine was present in a concentration which exceeded that of proline by a factor of six and that of phenylalanine by a factor of 100. This finding is consistent with the incorporation ratios of these amino acids into ergotamine when isotope dilution of the added radiolabel is considered. A significant stimulation of incorporation of constituent amino acids into ergotamine and ergocryptine occurred when d-lysergic acid was added to protoplasts and mycelium.
- Received:
- Revised:
- Published Online: