Tryptophan Camptotheca acuminata

Indole alkaloids Tryptophane decarboxylase Catharanthus roseus Camptotheca acuminata... 

LOPEZ-MEYER, M., NESSLER, C.L., Tryptophan decarboxylase is encoded by two autonomously regulated genes in Camptotheca acuminata which are... 

Luca, 1993). Its identity was confirmed by expression in . coli and N. tahacum (De Luca, 1993 Songstad et al, 1990). TDC is capable of decarboxylating both L-tryptophan and L-tyrosine in vivo. The tdc occurred as a single copy in C. roseus and the protein, when isolated, was found to be similar to that found in parsley and the fruitfly, except that it was found to lack 13 N-terminal amino acids compared with TDC from these sources. This suggested a processing of TDC protein in C. roseus and Camptotheca acuminata, from which it has also been isolated (Goddijn, 1992). However, this cleaved form acts as a functional enzyme and confirms that TDC is a cytosolic enzyme (De Luca, 1993 Stevens et al., 1993). The 13 N-terminal amino acids present in other TDC probably function as a signal peptide for membrane insertion or translocation. 

Among the alkaloids in this chapter derived from tryptophan, some do not retain the original nucleus of tryptophan, such as quinine, obtained from Cinchona plants (Rubiaceae), camptothecin, originally from Camptotheca acuminata (Cornaceae), and pyrrolnitrin of microbial origin. 

Tryptophan decarboxylase (TDC) Camptotheca acuminata, Catharanthus roseus... 

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