SUBCELLULAR-LOCALIZATION OF TRYPTOPHAN DECARBOXYLASE, STRICTOSIDINE SYNTHASE AND STRICTOSIDINE GLUCOSIDASE IN SUSPENSION-CULTURED CELLS OF CATHARANTHUS-ROSEUS AND TABERNAEMONTANA-DIVARICATA
Lh. Stevens et al., SUBCELLULAR-LOCALIZATION OF TRYPTOPHAN DECARBOXYLASE, STRICTOSIDINE SYNTHASE AND STRICTOSIDINE GLUCOSIDASE IN SUSPENSION-CULTURED CELLS OF CATHARANTHUS-ROSEUS AND TABERNAEMONTANA-DIVARICATA, Plant cell reports, 12(10), 1993, pp. 573-576
The subcellular localization of tryptophan decarboxylase, strictosidin
e synthase and strictosidine glucosidase in suspension cultured cells
of Catharanthus roseus (L.) G. Don and Tabernaemontana divaricata (L.)
R. Br. ex Roem. et Schult. was investigated. It was found that trypto
phan decarboxylase is an extra-vacuolar enzyme, whereas strictosidine
synthase is active inside the vacuole. Strong indications were obtaine
d for the localization of strictosidine glucosidase on the outside of
the tonoplast. The results suggest that tryptamine is transported into
the vacuole where it is condensed with secologanin to form strictosid
ine, and that strictosidine passes the tonoplast and is subsequently h
ydrolysed outside the vacuole.