4.1.99.1: tryptophanase
This is an abbreviated version!
For detailed information about tryptophanase, go to the full flat file.
Word Map on EC 4.1.99.1
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4.1.99.1
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quinonoid
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transposase
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aldimine
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proteus
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phenol-lyase
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thermonuclease
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beta-elimination
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l-trp
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tryptophan-induced
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antitermination
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pyridoxal-p
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rho-dependent
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rapid-scanning
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phillips
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alvei
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analysis
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food industry
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biotechnology
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drug development
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medicine
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synthesis
- 4.1.99.1
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quinonoid
- transposase
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aldimine
- proteus
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phenol-lyase
- thermonuclease
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beta-elimination
- l-trp
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tryptophan-induced
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antitermination
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pyridoxal-p
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rho-dependent
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rapid-scanning
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phillips
- alvei
- analysis
- food industry
- biotechnology
- drug development
- medicine
- synthesis
Reaction
Synonyms
L-tryptophan indole-lyase, L-tryptophanase, TIL, tna2, TnaA, tnaA2, TNase, Tpase, Trpase, tryptophan indole lyase, tryptophan indole-lyase, tryptophan-indole lyase, tryptophanase, tryptophanase 2, VcTrpase
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General Information on EC 4.1.99.1 - tryptophanase
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GENERAL INFORMATION 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
evolution
malfunction
a truncated TnaA protein containing only domains D1 and D3 (D1D3) localizes to the cell pole. Mutations affecting the D1D3-to-D1D3 interface do not affect polar localization of D1D3 but do delay assembly of wild-type TnaA foci. In contrast, alterations to the D1D3-to-D2 domain interface produce diffuse localization of the D1D3 variant but do not affect the wild-type protein. Altering several surface-exposed residues decreases TnaA activity, implying that tetramer assembly may depend on interactions involving these sites. Changing any of three amino acids at the base of a loop near the catalytic pocket decreases TnaA activity and causes it to form elongated ovoid foci in vivo, indicating that the alterations affect focus formation and may regulate how frequently tryptophan reaches the active site. Mutant phenotypes, detailed overview
metabolism
physiological function
additional information
evolution
residue Phe464 in Escherichia coli TIL is homologous to Phe459 in Proteus vulgaris TIL
evolution
residue Phe464 in Escherichia coli TIL is homologous to Phe459 in Proteus vulgaris TIL
evolution
the carbon-carbon lyases, tryptophan indole lyase (TIL) and tyrosine phenol-lyase (TPL, EC 4.1.99.2) are bacterial enzymes which catalyze the reversible elimination of indole and phenol from L-tryptophan and L-tyrosine, respectively. These pyridoxal 5'-phosphate-dependent enzymes show high sequence homology (about 40% identity) and both form homotetrameric structures. Pre-steady state kinetics with TPL and TIL show rapid formation of external aldimine intermediates, followed by deprotonation to give quinonoid intermediates absorbing at about 500 nm. The active sites of TIL and TPL are highly conserved with the exceptions of these residues: Arg381(TPL)/Ile396 (TIL), Thr124 (TPL)/Asp137 (TIL), and Phe448 (TPL)/His463 (TIL). The conserved tyrosine, Tyr71 (TPL)/Tyr74 (TIL) is essential for elimination activity with both enzymes, and likely plays a role as a proton donor to the leaving group. A unique feature of TIL and TPL is another strictly conserved lysine immediately preceding the pyridoxal 5'-phosphate-binding lysine, and hydrogen bonded to a water molecule bound to the monovalent cation. The mechanisms of TPL and TIL require both substrate strain and acid/base catalysis, and substrate strain is probably responsible for the very high substrate specificity of TPL and TIL. Both enzymes require a monovalent cation, either K+, NH4+, Rb+ or Cs+ for activity, with Na+ and Li+ giving little or no activity. The active site residues involved in PLP binding are highly conserved for both TIL and TPL. Sequence comparisons
evolution
the carbon-carbon lyases, tryptophan indole lyase (TIL) and tyrosine phenol-lyase (TPL, EC 4.1.99.2) are bacterial enzymes which catalyze the reversible elimination of indole and phenol from L-tryptophan and L-tyrosine, respectively. These pyridoxal 5'-phosphate-dependent enzymes show high sequence homology (about 40% identity) and both form homotetrameric structures. Pre-steady state kinetics with TPL and TIL show rapid formation of external aldimine intermediates, followed by deprotonation to give quinonoid intermediates absorbing at about 500 nm. The active sites of TIL and TPL are highly conserved with the exceptions of these residues: Arg381(TPL)/Ile396 (TIL), Thr124 (TPL)/Asp137 (TIL), and Phe448 (TPL)/His463 (TIL). The conserved tyrosine, Tyr71 (TPL)/Tyr74 (TIL) is essential for elimination activity with both enzymes, and likely plays a role as a proton donor to the leaving group. A unique feature of TIL and TPL is another strictly conserved lysine immediately preceding the pyridoxal 5'-phosphate-binding lysine, and hydrogen bonded to a water molecule bound to the monovalent cation. The mechanisms of TPL and TIL require both substrate strain and acid/base catalysis, and substrate strain is probably responsible for the very high substrate specificity of TPL and TIL. Both enzymes require a monovalent cation, either K+, NH4+, Rb+ or Cs+ for activity, with Na+ and Li+ giving little or no activity. The active site residues involved in PLP binding are highly conserved for both TIL and TPL. Sequence comparisons
metabolism
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indole production requires TnaB responsible for exogenous L-tryptophan import
metabolism
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tryptophanase is an initial enzyme for the degradation of L-tryptophan and 5-hydroxytryptophan in Escherichia coli
metabolism
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indole production requires TnaB responsible for exogenous L-tryptophan import
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physiological function
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Hfq protein associates with tryptophanase under relatively higher extracellular indole levels, suggesting this is a feedback control of indole production
physiological function
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tryptophan indole lyase produces indole from L-tryptophan, indole is a signaling molecule in bacteria, affecting biofilm formation, pathogenicity and antibiotic resistance
physiological function
the enzyme is responsible for the production of indole, an important intra- and interspecies signaling molecule in bacteria
physiological function
the Escherichia coli enzyme tryptophanase (TnaA) converts tryptophan to indole, which triggers physiological changes and regulates interactions between bacteria and their mammalian hosts. Tryptophanase production is induced by external tryptophan, but the activity of TnaA is also regulated by other mechanisms. TnaA activity is regulated by subcellular localization and by a loop-associated occlusion of its active site, formation of TnaA foci might regulate TnaA function. Model of post-translational regulation of TnaA activity by focus formation, overview
physiological function
the metabolic enzyme tryptophanase (TPase) is able to convert an odorless substrate like S-methyl-L-cysteine or L-tryptophan into the odorous products methyl mercaptan or indole
physiological function
tryptophanase is a bacterial enzyme involved in the degradation of tryptophan to indole, pyruvate and ammonia, which are compounds that are essential for bacterial survival. Tryptophanase is often overexpressed in stressed cultures
physiological function
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tryptophan indole lyase produces indole from L-tryptophan, indole is a signaling molecule in bacteria, affecting biofilm formation, pathogenicity and antibiotic resistance
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physiological function
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the enzyme is responsible for the production of indole, an important intra- and interspecies signaling molecule in bacteria
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additional information
determination of residues that affect assembly and localization of TnaA foci, overview
additional information
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determination of residues that affect assembly and localization of TnaA foci, overview
additional information
eight catalytically important residues Thr52, Tyr74, Arg103, Asp137, Arg230, Lys269, Lys270, and His463 are located close to the Trpase active site and are absolutely conserved in Trpases. Five of them are located in the conserved regions and are reported to confer a crucial role for binding of the substrate and cofactor to produce the formation of the best intermediate that will lead to substrate degradation. Despite the apparent diversity in the protein sequences, these regions may be essential for enzyme activity to generate indole, which is an important agent for bacterial physiology, ecological balance, and virulence
additional information
the conformation of all holo subunits is the same in both crystal forms. The structures suggest that Trpase is flexible in the apoform. Its conformation partially closes upon binding of PLP. The closed conformation might correspond to the enzyme in its active state with both cofactor and substrate bound in a similar way as in tyrosine phenol-lyase
additional information
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the conformation of all holo subunits is the same in both crystal forms. The structures suggest that Trpase is flexible in the apoform. Its conformation partially closes upon binding of PLP. The closed conformation might correspond to the enzyme in its active state with both cofactor and substrate bound in a similar way as in tyrosine phenol-lyase
additional information
the conserved Phe449 in TPL locates within 3 A of the substrate aromatic ring in the closed conformation
additional information
the conserved Phe459 in TPL locates within 3 A of the substrate aromatic ring in the closed conformation. Asp133 may be the residue that contacts the substrate
additional information
the reaction intermediate quinonoid complex of pyridoxal 5'-phosphate with L-tryptophan is modeled, based on the structure with inhibitor oxindolyl-L-alanine, by replacement of the oxindole ring with indole, and then docked manually into the active site by overlaying the pyridoxal 5'-phosphate rings of OIP and the L-tryptophan-pyridoxal 5'-phosphate complex
additional information
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the reaction intermediate quinonoid complex of pyridoxal 5'-phosphate with L-tryptophan is modeled, based on the structure with inhibitor oxindolyl-L-alanine, by replacement of the oxindole ring with indole, and then docked manually into the active site by overlaying the pyridoxal 5'-phosphate rings of OIP and the L-tryptophan-pyridoxal 5'-phosphate complex
additional information
tryptophanase-positive Symbiobacterium thermophilum is a free-living syntrophic bacterium that grows effectively in a coculture with Geobacillus stearothermophilus, indole accumulation occurs when bicarbonate is added to the medium. The transcription of some genes involved in amino acid metabolism is sigma54-dependent, and a bacterial enhancer-binding protein containing a PAS domain controls the transcription under the presence of high levels of bicarbonate. sigma54-Dependent expression of tryptophanase in Symbiobacterium thermophilum, overview
additional information
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tryptophanase-positive Symbiobacterium thermophilum is a free-living syntrophic bacterium that grows effectively in a coculture with Geobacillus stearothermophilus, indole accumulation occurs when bicarbonate is added to the medium. The transcription of some genes involved in amino acid metabolism is sigma54-dependent, and a bacterial enhancer-binding protein containing a PAS domain controls the transcription under the presence of high levels of bicarbonate. sigma54-Dependent expression of tryptophanase in Symbiobacterium thermophilum, overview
additional information
Symbiobacterium thermophilum T / IAM 14863 / JCM 14929
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tryptophanase-positive Symbiobacterium thermophilum is a free-living syntrophic bacterium that grows effectively in a coculture with Geobacillus stearothermophilus, indole accumulation occurs when bicarbonate is added to the medium. The transcription of some genes involved in amino acid metabolism is sigma54-dependent, and a bacterial enhancer-binding protein containing a PAS domain controls the transcription under the presence of high levels of bicarbonate. sigma54-Dependent expression of tryptophanase in Symbiobacterium thermophilum, overview
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additional information
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eight catalytically important residues Thr52, Tyr74, Arg103, Asp137, Arg230, Lys269, Lys270, and His463 are located close to the Trpase active site and are absolutely conserved in Trpases. Five of them are located in the conserved regions and are reported to confer a crucial role for binding of the substrate and cofactor to produce the formation of the best intermediate that will lead to substrate degradation. Despite the apparent diversity in the protein sequences, these regions may be essential for enzyme activity to generate indole, which is an important agent for bacterial physiology, ecological balance, and virulence
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