ACTIVITIES OF CHORISMATE UTILIZING ENZYMES AND OF ENZYMES INVOLVED IN INDOLE ALKALOID BIOSYNTHESIS IN CELL-SUSPENSION CULTURES

Cell suspension cultures of Catharanthus roseus, Tabernaemontana divaricata, Tabernaemontana pandacaqui, Cinchona robusta, Rubia tinctorum and Euonymus europaeus, representing 3 different plant families, were compared with respect to indole alkaloid production and specific activities of the enzymes: chorismate mutase (CM, EC5.4.99.5), isochorismate synthase (ISC, EC5.4.99.6), anthranilate synthase (AS, EC4.1.3.27), tryptophan decarboxylase (TDC, EC4.1.1.28) and strictosidine synthase (SSS, EC4.3.3.2). AS and CM were present in all the six cell cultures. ISC was present in R. tinctorum cells producing anthraquinones, in a green C. roseus cell culture and in T. divaricata cells. TDC was only present in a C. roseus cell culture accumulating tryptamine and in a T. divaricata cell culture producing small amounts of vallesamine and o-acetylvallesamine. SSS was absent from E. europaeus and R. tinctorum. In C.roseus ISC, AS, TDC and SSS were induced after transfer to induction media for indole alkaloid production.