Tryptophan Catharanthus roseus

Indole alkaloids Tryptophane decarboxylase Catharanthus roseus Camptotheca acuminata... 

Gene transfer from the angiosperm Catharanthus roseus, and over-expression in the bacterium Escherichia coli, yielded the synthase for strictosidine, a known alkaloid of the tryptophan-secologanin class (Scott 1992). A similar strategy has clarifted the biosynthesis of hydrogenobyrinic acid, an advanced precursor of vitamin B,2 (Scott 1994). 

Within the natural products field, the investigation of complete biosynthetic pathways at the enzyme level has been especially successful for plant alkaloids of the monoterpenoid indole alkaloid family generated from the monoterpene gluco-side secologanin and decarboxylation product of tryptophan, tryptamine [3-5]. The most comprehensive enzymatic data are now available for the alkaloids ajmalicine (raubasine) from Catharanthus roseus, and for ajmaline from Indian Rauvolfia serpentina [6] the latter alkaloid with a six-membered ring system bearing nine chiral carbon atoms. Entymatic data exsist also for vindoline, the vincaleucoblastin (VLB) precursor for which some studies on enzymatic coupling of vindoline and catharanthine exist in order to get the so-called dimeric Catharanthus indole-alkaloids VLB or vincristine [7-9] with pronounced anti-cancer activity [10, 11]. 

Ouwerkerk, P. B. F., Hallard, D., Verpoorte, R., and Memelink, J., Identification of UV-B light-responsive regions in the promoter of the tryptophan decarboxylase gene from Catharanthus roseus, Plant Mol. Biol., 41, 491, 1999. 

Figure 7.7 The relative location of c/s-elements and putative transcriptional regulators on the tryptophan decarboxylase (TDC), strictosidine synthase (STR), and cytochrome P450 reductase (CPR) gene promotors from Catharanthus roseus. The black box represents elements responsive to elicitor, jasmonate, or UV light. The white box represents a G-box motif, whereas the striped box represents a GCC-box element.

EILERT, U., DE LUCA, V., CONSTABEL, F., KURZ, W.G.W., Elicitor-mediated induction of tryptophan decarboxylase and strictosidine synthase activities in cell suspension cultures of Catharanthus roseus. Arch Biochem. Biophys., 1987, 254,491-497. 

CANEL, C., LOPES-CARDOSO, M.I., WH1TMER, S VAN DER FITS, L., PASQUALI, G., VAN DER HEIJDEN, R HOGE, J.H., VERPOORTE, R., Effects of over-expression of strictosidine synthase and tryptophan decarboxylase on alkaloid production by cell cultures of Catharanthus roseus. Planta, 1998,205, 414-419. 

STEVENS, L.H., BLOM, T.J.M., VERPOORTE, R., Subcellular localization of tryptophan decarboxylase, strictosidine synthase and strictosidine glucosidase in suspension cultured cells of Catharanthus roseus and Tabemaemontana divaricata. Plant Cell Rep., 1993,12, 563-576. 

Fig. 8.1 Sequence of reactions and pathways involved in the biosynthesis of indole alkaloids in Catharanthus roseus. The dotted lines indicate multiple and/or uncharacterized enzyme steps. Tryptophan decarboxylase (TDC), Geraniol Hydroxylase (GH), Deoxyloganin synthase (DS), Secologanin Synthase (SLS) Strictosidine synthase (STR1), Strictosidine glucosidase (SG), Tabersonine-16-hydroxylase (T16H), Tabersonine 6,7-eposidase (T6,7E), Desacetoxyvindoline-4-hydroxylase (D4H), Deacetyl-vindoline-4-O-acetyltransferase (DAT) and Minovincinine-19-O-acetyltransferase (MAT) represent some of the enzyme steps that have been characterized.

Tryptamine has been identified as a native compound in tomato,132 and the gene encoding tryptophan decarboxylase has been isolated from Catharanthus roseus,133 Plants grown on deuterium oxide incorporated more label into tryptamine than IAA, which was consistent with the result expected for a precursor of IAA. IAOx may be a YUCCA pathway intermediate for IAA biosynthesis in A. thaliana, and perhaps in rice and maize as well however, no enzyme has yet been identified for the conversion of A-hydroxyl tryptamine to IAOx. Because tryptamine is not a compound universally present in plants69 and deuterium oxide labeling ruled out tryptamine as an intermediate in tomato,132 the pathway would have to be species-specific. 

Fernandez, J.A., Owen, T.G., Kurz, W.G.W. and De Luca, V. (1989) Immunological detection and quantitation of tryptophan decarboxylase in developing Catharanthus roseus seedlings. Plant Physiol, 91, 79-84. 

Pennings, E.J.M., Groen, B.W., Duine, J.A. and Verpoorte, R. (1989) Tryptophan decarboxylase from Catharanthus roseus is a pyridoxo-quinoprotein. FEBS Lett., 255, 97-100. 

Roewer, LA., Cloutier, N., Nessler, C.L. and De Luca, V. (1992) Transient induction of tryptophan decarboxylase (TEXT) and strictosidine synthase (SS) genes in cell suspension cultures of Catharanthus roseus. Plant Cell Rep., 11, 86-9. 

Much more complex are the thousands of alkaloids that include an indole (or 2,3-dihydroindole) sub-unit and in each of these one can discern the tryptamine nnit of the biosynthetic precursor tryptophan strychnine (33.3.2) (Strychnos nux vomica), vincristine (33.7) (Catharanthus roseus), and the antipsychotic and antihypertensive reserpine (Rauwolfia serpentina) are examples. A group of amides of lysergic acid, for example, ergotamine, occur in ergot fnngi (e.g. Claviceps purpurea), the remainder of the molecule comprising proline, phenylalanine and alanine nnits. Lysergic acid diethylamide is the notorious LSD. 

Fig. (4). Early steps of the biosynthesis of terpenoid indole alkaloids in Catharanthus roseus. Triple arrowheads indicate multiple steps. G10H geraniol 16-hydroxylase TDC tryptophan decarboxylase STR strictosidine synthase.

Tryptophan decarboxylase Catharanthus roseus pyridoxal-5 -phosphate decarboxylase aOD-E... 

Ftunandez JA, Kurz WGW, De Luca V (1989) Conformation dependent inactivation of tryptophan decarboxylase fiorn Catharanthus roseus. Biochem Cell Biol 67 730-734. doi 10.1139/089-109... 

Islas-Flores IR, Loyola-Vargas VM, Miranda-Ham ML (1994) Tryptophan decarboxylase activity in transformed roots fiorn Catharanthus roseus and its relationship to tryptamine, ajmalicine, and catharanthine accumulation during the culture cycle. In Vitro Cell Dev Biol... 

Goddijn OJM, de Kam RJ, Zanetti A, Schilperorut RA, Hoge JHC (1992) Auxin rapidly down-regulates transcription of the tryptophan decarboxylase gene fiorn Catharanthus roseus. Plant Mol Biol 18 1113-1120. doi 10.1007/BF00047714... 

Whitmer S, van der Heijden R, Verpoorte R (2002) Effect of precursor feeding on alkaloid accumulation by a tryptophan decarboxylase over-expressing transgenic cell line T22 of Catharanthus roseus. J Biotechnol 96 193-203. doi 10.1016/S0168-1656(02)00027-5... 

Geerlings A, Hallard D, Caballero AM, Cardoso IL (1999) Alkaloid production by a Cinchona officinalis Ledgeriana hairy root culture containing constitutive expression constructs of tryptophan decarboxylase and strictosidine synthase cDNAs from Catharanthus roseus. Plant Cell Rep 19 191-196. doi 10.1007/s002990050732... 

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

Nicotiana tabacum Catharanthus roseus Tryptophan decarboxylase (TDC) Increased tryptamine... 

Nicotiana tabacum Catharanthus roseus Tryptophan decarboxylase (TDC), Strictosidine synthase (STR) Strictosidine production when supplied with exogenous secologanin... 

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