This view shows enzymes only for those organisms listed below, in the list of taxa known to possess the pathway. If an enzyme name is shown in bold, there is experimental evidence for this enzymatic activity.
|Superclasses:||Biosynthesis → Secondary Metabolites Biosynthesis → Nitrogen-Containing Secondary Compounds Biosynthesis|
|Biosynthesis → Secondary Metabolites Biosynthesis → Nitrogen-Containing Secondary Compounds Biosynthesis → Alkaloids Biosynthesis|
|Degradation/Utilization/Assimilation → Amino Acids Degradation → Proteinogenic Amino Acids Degradation → L-tryptophan Degradation|
Some taxa known to possess this pathway include : Arabidopsis thaliana col, Azospirillum brasilense, Bacillus cereus, Bacillus sp. No. 230, Brachybacterium conglomeratum, Catharanthus roseus, Enterococcus faecalis, Micrococcus percitreus , Rhizobium phaseoli
Tryptamine is an important molecule in eukaryotes. In mammals, tryptamine is an endogenous neuroactive metabolite of tryptophan, with behavioral, physiological and pharmacological effects [Mousseau93]. In plants, tryptamine is a merging point of primary and secondary metabolism. Tryptamine, which is derived from tryptophan by the action of tryptophan decarboxylase, provides the indole unit of monoterpenoid-indole and derived alkaloids, many of which are psychoactive [Patten96, Whitmer98]. Tryptophan decarboxylase has been cloned from Catharanthus roseus, and overexpressed in Nicotiana tabacum; it resulted in high tryptamine levels, and resistance to whitefly [Thomas95].
The pathway is widely spread in plants and fungi [Patten96], but little information is available about tryptamine in bacterial metabolism.
Mitoma and Udenfriend [Mitoma60] have demonstrated that strains of Enterococcus faecalis possess tryptophan decarboxylase activity, transforming tryptophan to tryptamine. However, since their enzyme preparation also had tyrosine and phenylalanine decarboxylase activity, and taking into account the very high Km that enzyme had for tryptophan (13 mM) , they were not sure whether tryptophan decarboxylation in that organism was a result of a distinct enzyme or an activity of aromatic L-amino acid decarboxylase (EC 184.108.40.206).
Perley and Stowe [Perley66] demonstrated production of tryptamine from tryptophan by Bacillus cereus strain KVT. The enzyme required pyridoxal phosphate as a cofactor, and had an optimum pH of 8.0. Buki et al [Buki85] isolated and partially purified a tryptophan decarboxylase from another Bacillus strain.
Nakazawa et al detected an aromatic L-amino acid decarboxylase in several bacterial species, which was highly active against tryptophan, forming tryptamine [Nakazawa74, Nakazawa77]. The highest activity was detected in several Micrococcus species. The carboxylase was produced constitutively, but was repressed by high concentrations of tryptamine.
It has been suggested that the soil bacterium Azospirillum brasilense, which lives in association with the roots of grasses and cereals, possesses a pathway for the production of IAA from tryptophan via tryptamine [Hartmann83, CarrenoLopez00]. The organism was able to convert tryptamine, which was added to the growth medium, to IAA, but no enzyme has been identified.
Variants: L-tryptophan degradation I (via anthranilate), L-tryptophan degradation II (via pyruvate), L-tryptophan degradation III (eukaryotic), L-tryptophan degradation IV (via indole-3-lactate), L-tryptophan degradation VII (via indole-3-pyruvate), L-tryptophan degradation VIII (to tryptophol), L-tryptophan degradation IX, L-tryptophan degradation to 2-amino-3-carboxymuconate semialdehyde, L-tryptophan degradation V (side chain pathway), L-tryptophan degradation X (mammalian, via tryptamine), L-tryptophan degradation XI (mammalian, via kynurenine), L-tryptophan degradation XII (Geobacillus)
Unification Links: AraCyc:PWY-3181
CarrenoLopez00: Carreno-Lopez R, Campos-Reales N, Elmerich C, Baca BE (2000). "Physiological evidence for differently regulated tryptophan-dependent pathways for indole-3-acetic acid synthesis in Azospirillum brasilense." Mol Gen Genet 264(4);521-30. PMID: 11129057
Whitmer98: Whitmer S, Canel C, Hallard D, Goncalves C, Verpoorte R (1998). "Influence of Precursor Availability on Alkaloid Accumulation by Transgenic Cell Line of Catharanthus roseus." Plant Physiol 116(2);853-7. PMID: 9490777
Burkhard01: Burkhard P, Dominici P, Borri-Voltattorni C, Jansonius JN, Malashkevich VN (2001). "Structural insight into Parkinson's disease treatment from drug-inhibited DOPA decarboxylase." Nat Struct Biol 8(11);963-7. PMID: 11685243
De89: De Luca V, Marineau C, Brisson N (1989). "Molecular cloning and analysis of cDNA encoding a plant tryptophan decarboxylase: comparison with animal dopa decarboxylases." Proc Natl Acad Sci U S A 86(8);2582-6. PMID: 2704736
Fernandez89: Fernandez, J.A., Owen, T.G., Kurz, W.G.W., De Luca, V.D. (1989). "Immunological detection and quantitation of tryptophan decarboxylase in developing Catharanthus roseus seedlings." Plant Physiol. 91: 79-84.
Ichinose85: Ichinose H, Kojima K, Togari A, Kato Y, Parvez S, Parvez H, Nagatsu T (1985). "Simple purification of aromatic L-amino acid decarboxylase from human pheochromocytoma using high-performance liquid chromatography." Anal Biochem 150(2);408-14. PMID: 4091266
Koiwai00: Koiwai H, Akaba S, Seo M, Komano T, Koshiba T (2000). "Functional expression of two Arabidopsis aldehyde oxidases in the yeast Pichia pastoris." J Biochem (Tokyo) 2000;127(4);659-64. PMID: 10739959
LopezMeyer97: Lopez-Meyer M, Nessler CL (1997). "Tryptophan decarboxylase is encoded by two autonomously regulated genes in Camptotheca acuminata which are differentially expressed during development and stress." Plant J 11(6);1167-75. PMID: 9225462
Ma02a: Ma J, Ito A (2002). "Tyrosine residues near the FAD binding site are critical for FAD binding and for the maintenance of the stable and active conformation of rat monoamine oxidase A." J Biochem 131(1);107-11. PMID: 11754741
Ma04a: Ma J, Yoshimura M, Yamashita E, Nakagawa A, Ito A, Tsukihara T (2004). "Structure of rat monoamine oxidase A and its specific recognitions for substrates and inhibitors." J Mol Biol 338(1);103-14. PMID: 15050826
Moore96: Moore PS, Dominici P, Borri Voltattorni C (1996). "Cloning and expression of pig kidney dopa decarboxylase: comparison of the naturally occurring and recombinant enzymes." Biochem J 315 ( Pt 1);249-56. PMID: 8670114
Noe84: Noe, W., Mollenschott, C., Berlin, J. (84). "Tryptophan decarboxylase from Catharanthus roseus cell suspension cultures: purification, molecular and kinetic data of the homogeneous protein." Plant Mol Biol 3: 281-288.
Seo00: Seo M, Peeters AJ, Koiwai H, Oritani T, Marion-Poll A, Zeevaart JA, Koornneef M, Kamiya Y, Koshiba T (2000). "The Arabidopsis aldehyde oxidase 3 (AAO3) gene product catalyzes the final step in abscisic acid biosynthesis in leaves." Proc Natl Acad Sci U S A 97(23);12908-13. PMID: 11050171
Seo98: Seo M, Akaba S, Oritani T, Delarue M, Bellini C, Caboche M, Koshiba T (1998). "Higher activity of an aldehyde oxidase in the auxin-overproducing superroot1 mutant of Arabidopsis thaliana." Plant Physiol 1998;116(2);687-93. PMID: 9489015
Wakagi02: Wakagi T, Fukuda E, Ogawa Y, Kino H, Matsuzawa H (2002). "A novel bifunctional molybdo-enzyme catalyzing both decarboxylation of indolepyruvate and oxidation of indoleacetaldehyde from a thermoacidophilic archaeon, Sulfolobus sp. strain 7." FEBS Lett 510(3);196-200. PMID: 11801253
Yamazaki03: Yamazaki Y, Sudo H, Yamazaki M, Aimi N, Saito K (2003). "Camptothecin biosynthetic genes in hairy roots of Ophiorrhiza pumila: cloning, characterization and differential expression in tissues and by stress compounds." Plant Cell Physiol 44(4);395-403. PMID: 12721380
Yao95: Yao K, De Luca V, Brisson N (1995). "Creation of a Metabolic Sink for Tryptophan Alters the Phenylpropanoid Pathway and the Susceptibility of Potato to Phytophthora infestans." Plant Cell 7(11);1787-1799. PMID: 12242360
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