Any feedback?
Please rate this page
(literature.php)
(0/150)

BRENDA support

Literature summary for 4.2.1.20 extracted from

  • Hettwer, S.; Sterner, R.
    A novel tryptophan synthase beta-subunit from the hyperthermophile Thermotoga maritima. Quaternary structure, steady-state kinetics, and putative physiological role (2002), J. Biol. Chem., 277, 8194-8201.
    View publication on PubMed

Cloned(Commentary)

Cloned (Comment) Organism
genes trpA, trpB1, and trpB2, expression in Escherichia coli Thermotoga maritima

KM Value [mM]

KM Value [mM] KM Value Maximum [mM] Substrate Comment Organism Structure
additional information
-
additional information steady state kinetics Thermotoga maritima
0.025
-
indole pH 7.5, 80°C, recombinant (TrpA-TrpB1)2 tetrameric complex, beta-reaction Thermotoga maritima
0.04
-
indole pH 7.5, 80°C, recombinant TrpB1, beta-reaction Thermotoga maritima
0.19
-
1-(indol-3-yl)glycerol 3-phosphate pH 7.5, 80°C, recombinant (TrpA-TrpB1)2 tetrameric complex, alpha-reaction Thermotoga maritima
1.62
-
1-(indol-3-yl)glycerol 3-phosphate pH 7.5, 80°C, recombinant TrpA, alpha-reaction Thermotoga maritima
3.7
-
L-serine pH 7.5, 80°C, recombinant (TrpA-TrpB1)2 tetrameric complex, beta-reaction Thermotoga maritima
110
-
L-serine pH 7.5, 80°C, recombinant TrpB1, beta-reaction Thermotoga maritima

Molecular Weight [Da]

Molecular Weight [Da] Molecular Weight Maximum [Da] Comment Organism
26200
-
recombinant TrpA monomer, sedimentation equilibrium Thermotoga maritima
91000
-
recombinant TrpB1 dimer, sedimentation equilibrium Thermotoga maritima
98000
-
recombinant TrpB2 dimer, sedimentation equilibrium Thermotoga maritima
140000
-
recombinant alphabetabetaalpha complex of TRpA and TrpB1, sedimentation equilibrium Thermotoga maritima

Organism

Organism UniProt Comment Textmining
Thermotoga maritima
-
hyperthermophile, alpha-subunit TrpA and beta-subunit TrpB1 are encoded by the 2 genes trpA and trpB1 in the trp operon, and by a trpB2 gene outside the operon
-

Purification (Commentary)

Purification (Comment) Organism
recombinant TrpA, TrpB1, and TrpB2 from Escherichia coli Thermotoga maritima

Reaction

Reaction Comment Organism Reaction ID
L-serine + 1-C-(indol-3-yl)glycerol 3-phosphate = L-tryptophan + D-glyceraldehyde 3-phosphate + H2O also catalyses the conversion of serine and indole into tryptophan and water, and of indoleglycerol phosphate into indole and glyceraldehyde phosphate (the latter reaction was listed formerly as EC 4.2.1.8) Thermotoga maritima

Substrates and Products (Substrate)

Substrates Comment Substrates Organism Products Comment (Products) Rev. Reac.
1-(indol-3-yl)glycerol 3-phosphate alpha-subunit of the bienzyme complex, alpha-reaction Thermotoga maritima D-glyceraldehyde 3-phosphate + indole
-
?
L-serine + indole beta-subunit of the bienzyme complex, beta-reaction Thermotoga maritima L-tryptophan + H2O
-
?
additional information indole is channeled to the active site of the beta-subunit, the TrpB2 homodimer has a high catalytic efficiency due to a low Km for indole, it functions as a rescue protein for indole to prevent the escape of the costly hydrophobic metabolite at the hig growing temperatures of the hyperthermophile Thermotoga maritima ?
-
?

Subunits

Subunits Comment Organism
dimer TrpB2 does not bind to the alpha-subunit and forms homodimers, TrpB1 alone forms homodimers Thermotoga maritima
monomer TrpA alone forms monomers Thermotoga maritima
More recombinantly expressed alpha-subunit forms monomers of 26.7 kDa, while the recombinant beta-subunits B1 and B2 both form dimers of 49.4 and 61.7 kDa, respectively Thermotoga maritima
tetramer alphabetabetaalpha complex of TRpA and TrpB1, sedimentation equilibrium Thermotoga maritima

Synonyms

Synonyms Comment Organism
TrpA
-
Thermotoga maritima
TrpB1
-
Thermotoga maritima
TrpB2
-
Thermotoga maritima

Temperature Optimum [°C]

Temperature Optimum [°C] Temperature Optimum Maximum [°C] Comment Organism
30 60 alpha-reaction assay at Thermotoga maritima
80
-
beta-reaction assay at Thermotoga maritima

Turnover Number [1/s]

Turnover Number Minimum [1/s] Turnover Number Maximum [1/s] Substrate Comment Organism Structure
0.174
-
1-(indol-3-yl)glycerol 3-phosphate pH 7.5, 80°C, recombinant TrpA, alpha-reaction Thermotoga maritima
3.8
-
L-serine pH 7.5, 80°C, recombinant TrpB1, beta-reaction Thermotoga maritima
4.2
-
indole pH 7.5, 80°C, recombinant TrpB1, beta-reaction Thermotoga maritima
5.6
-
1-(indol-3-yl)glycerol 3-phosphate pH 7.5, 80°C, recombinant (TrpA-TrpB1)2 tetrameric complex, alpha-reaction Thermotoga maritima
8
-
L-serine pH 7.5, 80°C, recombinant (TrpA-TrpB1)2 tetrameric complex, beta-reaction Thermotoga maritima
10
-
indole pH 7.5, 80°C, recombinant (TrpA-TrpB1)2 tetrameric complex, beta-reaction Thermotoga maritima

pH Optimum

pH Optimum Minimum pH Optimum Maximum Comment Organism
7.5
-
assay at Thermotoga maritima