Literature summary for 4.2.1.20 extracted from

Kulik, V.; Weyand, M.; Seidel, R.; Niks, D.; Arac, D.; Dunn, M.F.; Schlichting, I.
On the role of alphaThr183 in the allosteric regulation and catalytic mechanism of tryptophan synthase (2002), J. Mol. Biol., 324, 677-690.

Crystallization (Commentary)

Crystallization (Comment)	Organism
crystallization of wild-type enzyme alone and complexed with L-serine and 3-indolylpropanol 3'-phosphate, and of mutant T183V complexed with L-serine, 1-(indol-3-yl)glycerol 3-phosphate, and 3-indolylpropanol 3'-phosphate, hanging drop method in the dark at room temperature, equal volumes of protein solution, containing 10 mg/ml protein, 50 mM Na-bicine, pH 7.8, 10 mM Na-EDTA, 1 mM dithioerythritol, 0.02 mM pyridoxal 5'-phosphate, and of reservoir solution, containing 50 mM Na-bicine, pH 7.8, 5 mM dithioerythritol, 5 mM Na-EDTA, 0.1 mM pyridoxal 5'-phosphate, 2 mM spermine, 8-12% w/v PEG 8000, X-ray diffraction structure determination and analysis at different resolutions 1.45-2.3 A, comparison of crystal structures of the different complexes	Salmonella enterica subsp. enterica serovar Typhimurium

Crystallization (Comment)

Organism

crystallization of wild-type enzyme alone and complexed with L-serine and 3-indolylpropanol 3'-phosphate, and of mutant T183V complexed with L-serine, 1-(indol-3-yl)glycerol 3-phosphate, and 3-indolylpropanol 3'-phosphate, hanging drop method in the dark at room temperature, equal volumes of protein solution, containing 10 mg/ml protein, 50 mM Na-bicine, pH 7.8, 10 mM Na-EDTA, 1 mM dithioerythritol, 0.02 mM pyridoxal 5'-phosphate, and of reservoir solution, containing 50 mM Na-bicine, pH 7.8, 5 mM dithioerythritol, 5 mM Na-EDTA, 0.1 mM pyridoxal 5'-phosphate, 2 mM spermine, 8-12% w/v PEG 8000, X-ray diffraction structure determination and analysis at different resolutions 1.45-2.3 A, comparison of crystal structures of the different complexes

Salmonella enterica subsp. enterica serovar Typhimurium

Protein Variants

Protein Variants	Comment	Organism
T183V	site-directed mutagenesis, isosteric alpha-subunit mutant, exchange of a highly conserved residue, strongly impaired allosteric alpha-beta communication, 100fold reduced alpha-reaction activity, beta-reaction activity is not affected, effects are due to a missing hydrogen bind between alphaT183 and the catalytic residue alphaAsp60	Salmonella enterica subsp. enterica serovar Typhimurium

Inhibitors

Inhibitors	Comment	Organism	Structure
DL-glycerol 3-phosphate	inhibits the reaction of indole with the enzyme	Salmonella enterica subsp. enterica serovar Typhimurium

Organism

Organism	UniProt	Comment	Textmining
Salmonella enterica subsp. enterica serovar Typhimurium	-	-	-

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), reaction mechanism of alpha- and beta-reaction step, T183 and D60 are involved	Salmonella enterica subsp. enterica serovar Typhimurium	a

Specific Activity [micromol/min/mg]

Specific Activity Minimum [µmol/min/mg]	Specific Activity Maximum [µmol/min/mg]	Comment	Organism
additional information	-	-	Salmonella enterica subsp. enterica serovar Typhimurium

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.
1-(indol-3-yl)glycerol 3-phosphate	alpha-subunit of the bifunctional enzyme complex, alpha-reaction	Salmonella enterica subsp. enterica serovar Typhimurium	D-glyceraldehyde 3-phosphate + indole	-	?
L-serine + indole	beta-subunit of the bifunctional enzyme complex, beta-reaction	Salmonella enterica subsp. enterica serovar Typhimurium	L-tryptophan + H2O	-	?
L-serine + indoline	-	Salmonella enterica subsp. enterica serovar Typhimurium	dihydro-iso-L-tryptophan + H2O	i.e. DIT	?
additional information	allostery and substrate channeling, wild-type and mutant T183V	Salmonella enterica subsp. enterica serovar Typhimurium	?	-	?

Subunits

Subunits	Comment	Organism
tetramer	alpha2beta2 complex	Salmonella enterica subsp. enterica serovar Typhimurium

Synonyms

Synonyms	Comment	Organism
TRPS	-	Salmonella enterica subsp. enterica serovar Typhimurium

Turnover Number [1/s]

Turnover Number Minimum [1/s]	Turnover Number Maximum [1/s]	Substrate	Comment	Organism
0.00017	-	L-serine	overall-reaction, pH 7.8, 25°C, mutant T183V enzyme	Salmonella enterica subsp. enterica serovar Typhimurium
0.00017	-	1-(indol-3-yl)glycerol 3-phosphate	overall-reaction, pH 7.8, 25°C, mutant T183V enzyme	Salmonella enterica subsp. enterica serovar Typhimurium
0.00059	-	1-(indol-3-yl)glycerol 3-phosphate	alpha-reaction, pH 7.8, 25°C, mutant T183V enzyme	Salmonella enterica subsp. enterica serovar Typhimurium
0.063	-	1-(indol-3-yl)glycerol 3-phosphate	alpha-reaction, pH 7.8, 25°C, wild-type enzyme	Salmonella enterica subsp. enterica serovar Typhimurium
2.61	-	L-serine	overall-reaction, pH 7.8, 25°C, wild-type enzyme	Salmonella enterica subsp. enterica serovar Typhimurium
2.61	-	1-(indol-3-yl)glycerol 3-phosphate	overall-reaction, pH 7.8, 25°C, wild-type enzyme	Salmonella enterica subsp. enterica serovar Typhimurium
3	6	L-serine	overall-reaction, pH 7.8, 25°C, wild-type enzyme	Salmonella enterica subsp. enterica serovar Typhimurium
3	6	1-(indol-3-yl)glycerol 3-phosphate	overall-reaction, pH 7.8, 25°C, wild-type enzyme	Salmonella enterica subsp. enterica serovar Typhimurium
3.3	-	L-serine	beta-reaction, pH 7.8, 25°C, mutant T183V enzyme	Salmonella enterica subsp. enterica serovar Typhimurium
3.3	-	indole	beta-reaction, pH 7.8, 25°C, mutant T183V enzyme	Salmonella enterica subsp. enterica serovar Typhimurium
3.3	-	L-serine	beta-reaction, pH 7.8, 25°C, wild-type enzyme	Salmonella enterica subsp. enterica serovar Typhimurium
3.3	-	indole	beta-reaction, pH 7.8, 25°C, wild-type enzyme	Salmonella enterica subsp. enterica serovar Typhimurium
4.51	-	L-serine	beta-reaction, pH 7.8, 25°C, wild-type enzyme	Salmonella enterica subsp. enterica serovar Typhimurium
4.51	-	indole	beta-reaction, pH 7.8, 25°C, wild-type enzyme	Salmonella enterica subsp. enterica serovar Typhimurium
5.24	-	L-serine	beta-reaction, pH 7.8, 25°C, mutant T183V enzyme	Salmonella enterica subsp. enterica serovar Typhimurium
5.24	-	indole	beta-reaction, pH 7.8, 25°C, mutant T183V enzyme	Salmonella enterica subsp. enterica serovar Typhimurium

Cofactor

Cofactor	Comment	Organism	Structure
pyridoxal 5'-phosphate	dependent on, bound to the enzyme	Salmonella enterica subsp. enterica serovar Typhimurium