FB2026_01 , released March 12, 2026
FB2026_01 , released March 12, 2026
Pathway: L-TRYPTOPHAN CATABOLISM
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General Information
Name
L-TRYPTOPHAN CATABOLISM
Species
D. melanogaster
Symbol
TRYCAT
FlyBase ID
FBgg0002189
Date last reviewed
2025-01-27
Number of members
3
Description
Description
L-tryptophan is an essential amino acid. Besides its role in protein biosynthesis, L-tryptophan is converted in the cytosol to L-kynurenine, which is then used to synthesize eye pigment ommochromes. In addition, L-tryptophan is a precursor for the biosynthesis of neurotransmitter serotonin and melatonin. Unlike in mammals, L-tryptophan cannot be used to produce NAD(+) or catabolised to acetyl-CoA because Dmel has no homolog of kynureninase that converts L-kynurenine to 3-hydroxyanthranilate. (Adapted from FBrf0161620, FBrf0256069 and PMID:29989284.)
Notes
Source Material
The L-TRYPTOPHAN CATABOLISM Gene Group has been compiled using the following publication(s): Navrotskaya et al., 2018 .
Key Gene Ontology (GO) terms
Biological Process
L-tryptophan catabolic process
Cellular Component
cytosol
Related Gene Groups
Parent group(s)
AMINO ACID METABOLISM
GO Causal Activity Model (GO-CAM)
Members (3)
For all members:
GO ribbon stack
 molecular functionbiological processcellular component
External Data
Other resource(s)
Note: The Drosophila pathways shown at these resources are computed using different methods. They may therefore differ from the manually curated and verified pathway shown above.

[FlyCyc: L-tryptophan degradation to 2-amino-3-carboxymuconate semialdehyde](https://biocyc.org/pathway?orgid=DMEL&id=PWY-5651)

[Reactome: Tryptophan catabolism](https://reactome.org/PathwayBrowser/#/R-DME-71240)

[KEGG: Tryptophan metabolism](https://www.kegg.jp/pathway/dme00380)

Synonyms and Secondary IDs
Synonym(s)
TRYCAT
L-tryptophan catabolism
L-kynurenine biosynthesis
L-TRYPTOPHAN CATABOLISM
Secondary FlyBase ID(s)
References (2)