Information on EC 4.2.3.1 - threonine synthase

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The expected taxonomic range for this enzyme is: Eukaryota, Bacteria, Archaea

EC NUMBER
COMMENTARY
4.2.3.1
-
RECOMMENDED NAME
GeneOntology No.
threonine synthase
REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
O-phospho-L-homoserine + H2O = L-threonine + phosphate
show the reaction diagram
-
-
-
-
O-phospho-L-homoserine + H2O = L-threonine + phosphate
show the reaction diagram
reaction proceeds via phospate removal and isomerization from primary to secondary alcohol
-
O-phospho-L-homoserine + H2O = L-threonine + phosphate
show the reaction diagram
mechanism of phosphohomoserine dephosphorylation/deamination activity
-
O-phospho-L-homoserine + H2O = L-threonine + phosphate
show the reaction diagram
mechanism
-
O-phospho-L-homoserine + H2O = L-threonine + phosphate
show the reaction diagram
mechanism
-
O-phospho-L-homoserine + H2O = L-threonine + phosphate
show the reaction diagram
inhibitor studies concerning mechanism, model of stepwise catalytic mechanism
-
O-phospho-L-homoserine + H2O = L-threonine + phosphate
show the reaction diagram
mechanism
-
O-phospho-L-homoserine + H2O = L-threonine + phosphate
show the reaction diagram
mechanism
-
O-phospho-L-homoserine + H2O = L-threonine + phosphate
show the reaction diagram
reaction proceeds via phosphate removal and isomerization from primary to secondary alcohol
-
O-phospho-L-homoserine + H2O = L-threonine + phosphate
show the reaction diagram
reaction proceeds via phosphate removal and isomerization from primary to secondary alcohol
-
O-phospho-L-homoserine + H2O = L-threonine + phosphate
show the reaction diagram
reaction proceeds via phosphate removal and isomerization from primary to secondary alcohol
-
O-phospho-L-homoserine + H2O = L-threonine + phosphate
show the reaction diagram
analyzed crystal structure gives new insights into the catalytic mechanism of threonine synthase in general, specifically by suggesting the direct involvement of the phosphate moiety of the cofactor, rather than the inorganic phosphate product, in transferring a proton from C4 to Cgamma in the formation of the alphabeta-unsaturated aldimine
P66902
O-phospho-L-homoserine + H2O = L-threonine + phosphate
show the reaction diagram
the phosphate ion released from O-phospho-L-homoserine by gamma-elimination acts as the base catalyst for the addition of water at Cbeta of the alpha-aminocrotonate aldimine, thereby providing the basis of the reaction specificity. The phosphate ion also accelerates the protonation/deprotonation at Cgamma
Q5SL02
REACTION TYPE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
elimination
-
-
-
-
elimination
-
-
elimination
-
-
elimination
-
-
PATHWAY
KEGG Link
MetaCyc Link
Glycine, serine and threonine metabolism
-
Metabolic pathways
-
Microbial metabolism in diverse environments
-
threonine biosynthesis from homoserine
-
Vitamin B6 metabolism
-
SYSTEMATIC NAME
IUBMB Comments
O-phospho-L-homoserine phosphate-lyase (adding water; L-threonine-forming)
A pyridoxal-phosphate protein.
SYNONYMS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
EC 4.2.99.2
-
-
formerly
-
synthase, threonine
-
-
-
-
threonine synthase
-
-
threonine synthase
-
-
threonine synthase
-
-
threonine synthase
-
-
threonine synthase
P66902
-
threonine synthase
-
-
threonine synthase (gene MA1610)
-
-
threonine synthetase
-
-
-
-
CAS REGISTRY NUMBER
COMMENTARY
9023-97-6
-
ORGANISM
COMMENTARY
LITERATURE
SEQUENCE CODE
SEQUENCE DB
SOURCE
phylogenetic comparison to other Bacillus subtilis enzymes
-
-
Manually annotated by BRENDA team
wild type and various mutant enzymes
-
-
Manually annotated by BRENDA team
var. altissima
-
-
Manually annotated by BRENDA team
wild type and several methionine-overproducing strains
-
-
Manually annotated by BRENDA team
Hegelm. 6746
-
-
Manually annotated by BRENDA team
strain HB8
-
-
Manually annotated by BRENDA team
SUBSTRATE
PRODUCT                      
REACTION DIAGRAM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
(Substrate)
LITERATURE
(Substrate)
COMMENTARY
(Product)
LITERATURE
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
DL-3-chloroalanine
pyruvate + NH3 + HCl
show the reaction diagram
-
beta-elimination
-
ir
DL-vinylglycine + H2O
L-threonine
show the reaction diagram
-
-
-
ir
L-allo-threonine + H2O
2-oxobutyrate + NH3
show the reaction diagram
-
beta-elimination
-
ir
L-serine
pyruvate + NH3
show the reaction diagram
-
beta-elimination
-
ir
O-phospho-L-homoserine
?
show the reaction diagram
-
studies on regulatory properties
-
-
-
O-phospho-L-homoserine
?
show the reaction diagram
-
involved in allocation of phosphohomoserine between cystathione and threonine pathways
-
-
-
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
ir
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
ir
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
ir
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
ir
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
ir
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
ir
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
ir
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
ir
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
ir
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
ir
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
-
-
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
Q9S7B5
-
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
ir
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
ir
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
ir
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
ir
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
ir
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
ir
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
-
-
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
P66902
-
-
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
Q5SL02, -
-
reaction is 99% specific for L-threonine formation. Minor product is 2-ketobutanoate
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
enzyme at the metabolic branch point between methionine and threonine biosynthesis
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
final step of threonine biosynthesis
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
Q9S7B5
last reaction in the synthesis of threonine from aspartate
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
threonine synthesis in eukaryotes
-
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
threonine synthesis in eukaryotes
-
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
threonine synthesis in eukaryotes
-
-
?
phosphohomoserine
2-oxobutyrate + phosphate + ?
show the reaction diagram
-
bypass of threonine in isoleucine biosynthesis
-
ir
threonine
2-oxobutyrate + NH3
show the reaction diagram
-
-
-
ir
threonine
2-oxobutyrate + NH3
show the reaction diagram
-
beta-elimination
-
-
threonine
2-oxobutyrate + NH3
show the reaction diagram
-
genetic evidence for identity of protein with both activities
-
ir
L-vinylglycine + phosphate + H2O
L-threonine + phosphate
show the reaction diagram
Q5SL02, -
in the presence of phosphate, L-threonine is formed with kcat and reaction specificity comparable with those when O-phospho-L-homoserine is used as the substrate. In the absence of phosphate or when sulfate is used in place of phosphate, only the side reaction product, alpha-ketobutyrate, is formed. Compared with the more acidic sulfate ion, the phosphate ion decreases the energy levels of the transition states of the addition of water at the Cbeta of the PLP-alpha-aminocrotonate aldimine and the transaldimination to form L-threonine. Threonine synthase is in the closed form, when the substrate and the intermediates are bound to the enzyme
-
-
?
additional information
?
-
-
-
-
-
-
additional information
?
-
-
half-transamination reactions
-
-
-
NATURAL SUBSTRATES
NATURAL PRODUCTS
REACTION DIAGRAM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
(Substrate)
LITERATURE
(Substrate)
COMMENTARY
(Product)
LITERATURE
(Product)
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
O-phospho-L-homoserine
?
show the reaction diagram
-
studies on regulatory properties
-
-
-
O-phospho-L-homoserine
?
show the reaction diagram
-
involved in allocation of phosphohomoserine between cystathione and threonine pathways
-
-
-
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
enzyme at the metabolic branch point between methionine and threonine biosynthesis
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
final step of threonine biosynthesis
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
Q9S7B5
last reaction in the synthesis of threonine from aspartate
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
threonine synthesis in eukaryotes
-
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
threonine synthesis in eukaryotes
-
-
?
O-phospho-L-homoserine + H2O
L-threonine + phosphate
show the reaction diagram
-
threonine synthesis in eukaryotes
-
-
?
COFACTOR
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
pyridoxal 5'-phosphate
-
required cofactor
pyridoxal 5'-phosphate
-
-
pyridoxal 5'-phosphate
-
maximal activity at 0.4-1.0 mM; required cofactor
pyridoxal 5'-phosphate
-
-
pyridoxal 5'-phosphate
P66902
MtTS is not influenced by S-adenosylmethionine
pyridoxal 5'-phosphate
-
-
pyridoxal 5'-phosphate
Q5SL02
-
INHIBITORS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
AMP
-
50% inhibition at 40 mM, reversible, depends on phosphohomoserine concentration
AMP
-
same binding site as S-adenosylmethionine
AMP-derivatives
-
-
-
DL-2-amino-3[(phosphonomethyl)thio]propionic acid
-
Ki: 0.057 mM, kinact: 1.44 min-1
DL-E-2-amino-5-phosphono-4-pentenoic acid
-
Ki: 0.54 mM
GMP
-
25% inhibition at 67 mM
IMP
-
23% inhibition at 67 mM
KCN
-
22% inhibition at 1 mM
L-2,3-methanohomoserine phosphate
-
Ki: 0.01 mM
L-2-amino-3[(phosphonomethyl)thio]propionic acid
-
Ki: 0.00011 mM, 'slow, tight' inhibition kinetics
L-2-amino-3[(phosphonomethyl)thio]propionic acid
-
Ki: 0.011 mM
L-3-hydroxyhomoserine
-
Ki: 0.05 mM
L-cysteine
-
85% inhibition at 35 mM
L-cysteine
-
stereospecific, inhibits S-adenosylmethionine activation
L-cysteine
-
80% inhibition at 1 mM in presence of S-adenosylmethionine
L-cysteine
-
26% inhibition at 1 mM, reversible
L-cysteine
-
strong inhibition at 0.5 mM
L-threo-3-hydroxyhomoserine
-
marked inhibition at 5 mM, abolished by 60 mM Mg2+
L-threo-3-hydroxyhomoserine
-
Ki: 0.006 mM
NH2OH
-
65% inhibition at 1 mM
O-phospho-DL-threonine
-
-
O-phospho-L-serine
-
-
phosphate
-
40% inhibition at 50 mM
phosphate
-
50% inhibition at 1 mM, competitive, reversible, depends on phosphohomoserine concentration
phospho-threonine
-
35% inhibition at 10 mM
phosphonovaleric acid
-
Ki: 0.031 mM
-
Vinylglycine
-
22% inhibition at 10 mM
ACTIVATING COMPOUND
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
S-adenosyl-L-methionine
-
activates
S-adenosyl-L-methionine
-
-
S-adenosylmethionine
-
allosteric activator, 14fold increase of Vmax, 8% decrease of substrate Km at 0.5 mM
S-adenosylmethionine
-
allosteric activator, 4fold increase of Vmax, 3.3fold decrease of substrate Km at 0.4 mM
S-adenosylmethionine
-
allosteric activator, maximal activation at 0.1-0.2 mM
S-adenosylmethionine
-
3-20fold increase of specific activity in various recombinant enzymes at 0.2 mM
S-adenosylmethionine
-
same binding site as inhibitor AMP, 85fold increase of activity, maximum activity at 0.06-0.25 mM
S-adenosylmethionine
-
affects both Km and Vmax by allosteric and cooperative transition of enzyme, two mol per mol enzyme, 25fold decrease of Km at 0.06 mM
S-adenosylmethionine
-
activates
KM VALUE [mM]
KM VALUE [mM] Maximum
SUBSTRATE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
1.2
-
O-phospho-L-homoserine
P66902
-
0.03
-
O-phosphohomoserine
-
in presence of S-adenosylmethionine
0.12
-
O-phosphohomoserine
-
without S-adenosylmethionine
0.5
-
O-phosphohomoserine
-
-
1.3
2.7
O-phosphohomoserine
-
-
1.3
2.7
O-phosphohomoserine
-
-
0.002
0.007
O-phospohomoserine
-
at saturating S-adenosylmethionine concentrations
TURNOVER NUMBER [1/s]
TURNOVER NUMBER MAXIMUM[1/s]
SUBSTRATE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
0.61
-
L-Vinylglycine
Q5SL02
pH 8.0, 25C
0.8
-
O-phospho-L-homoserine
Q5SL02
pH 8.0, 25C
7.3
-
O-phospho-L-homoserine
P66902
-
4080
-
O-phospho-L-homoserine
-
-
0.0333
-
O-phosphohomoserine
-
without S-adenosylmethionine
0.4
-
O-phosphohomoserine
-
without S-adenosylmethionine
0.86
-
O-phosphohomoserine
-
in presence of S-adenosylmethionine
3.5
-
O-phosphohomoserine
-
at 0.06 mM S-adenosylmethionine
7.33
-
O-phosphohomoserine
-
-
0.034
-
phosphate
Q5SL02
pH 8.0, 25C
kcat/KM VALUE [1/mMs-1]
kcat/KM VALUE [1/mMs-1] Maximum
SUBSTRATE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
0.0059
-
L-Vinylglycine
Q5SL02
pH 8.0, 25C
12465
5.2
-
O-phospho-L-homoserine
Q5SL02
pH 8.0, 25C
14712
0.0013
-
phosphate
Q5SL02
pH 8.0, 25C
27500
Ki VALUE [mM]
Ki VALUE [mM] Maximum
INHIBITOR
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
0.057
-
DL-2-amino-3[(phosphonomethyl)thio]propionic acid
-
kinact: 1.44 min-1
0.54
-
DL-E-2-amino-5-phosphono-4-pentenoic acid
-
-
0.01
-
L-2,3-methanohomoserine phosphate
-
-
0.011
-
L-2-amino-3[(phosphonomethyl)thio]propionic acid
-
-
0.05
-
L-3-hydroxyhomoserine
-
-
0.006
-
L-threo-3-hydroxyhomoserine
-
-
0.031
-
phosphonovaleric acid
-
-
-
SPECIFIC ACTIVITY [µmol/min/mg]
SPECIFIC ACTIVITY MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
0.00098
0.00246
-
purified enzyme from cloned gene
0.012
-
-
-
0.014
-
-
mutation Ile-3
0.018
-
-
wild type
0.0261
-
-
-
7.7
-
-
purified enzyme from cloned gene
8.8
-
-
mutation SprA-44
additional information
-
-
activity with addition of several amino acids to several mutant cell lines
additional information
-
-
homozygous line from plant 829-2 exhibits 10.1fold and 2.1fold higher activity without and with 0.2 mmol/l S-adenosyl methionine compared to wild type. Homozygous line from plant 829-9 exhibits 25.2fold and 3.8fold higher activity without and with 0.2 mmol/l S-adenosyl methionine compared to wild type. Homozygous line from plant 829-14 exhibits 6.5fold and 1.5fold higher activity without and with 0.2 mmol/l S-adenosyl methionine compared to wild type
additional information
-
-
threonine synthase is significantly increased in recombinant overexpressing cells compared to expression in wild-type plants, ranging from 4.3fold in cell line S4, 5.1fold in cell line S3 and 7.1fold in cell line S1
pH OPTIMUM
pH MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
7.3
-
-
enzyme assay at
7.3
-
-
enzyme assay at
7.3
-
-
enzyme assay at
7.4
-
-
-
7.5
-
-
enzyme assay at
7.5
-
-
enzyme assay at
7.8
-
-
enzyme assay at, recombinant enzyme
8
-
-
enzyme assay at
8
-
-
enzyme assay at
8.4
-
P66902
assay at
8.5
-
-
enyzme assay at
pH RANGE
pH RANGE MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
6.8
8.4
-
-
TEMPERATURE OPTIMUM
TEMPERATURE OPTIMUM MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
20
-
-
enzyme assay at
25
-
P66902
assay at
30
-
-
enzyme assay at
30
-
-
enzyme assay at
30
-
-
enzyme assay at
30
-
-
enzyme assay at
35
-
-
enzyme assay at
37
-
-
enzyme assay at, recombinant enzyme
pI VALUE
pI VALUE MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
6.6
-
-
calculated
SOURCE TISSUE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
SOURCE
-
suspension culture of Nicotiana tabacum cells expressing E. coli enzyme
Manually annotated by BRENDA team
-
rosette leaves
Manually annotated by BRENDA team
LOCALIZATION
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
GeneOntology No.
LITERATURE
SOURCE
-
not exclusively in stroma
Manually annotated by BRENDA team
PDB
SCOP
CATH
ORGANISM
Aquifex aeolicus (strain VF5)
Brucella melitensis biotype 1 (strain 16M / ATCC 23456 / NCTC 10094)
Burkholderia thailandensis (strain E264 / ATCC 700388 / DSM 13276 / CIP 106301)
Escherichia coli (strain K12)
Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
Thermus thermophilus (strain HB8 / ATCC 27634 / DSM 579)
Thermus thermophilus (strain HB8 / ATCC 27634 / DSM 579)
MOLECULAR WEIGHT
MOLECULAR WEIGHT MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
46000
48000
-
gel filtration
53000
-
-
gel filtration
110000
-
-
gel filtration
135000
-
-
gel filtration
190000
-
-
gel filtration
SUBUNITS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
?
-
x * 57200, calculated
dimer
-
2 * 58000, comparison of nucleotide sequence and molecular mass of native enzyme
dimer
-
2 * 58000, comparison of nucleotide sequence and molecular mass of native enzyme; N-terminal amino acids involved in dimerization
dimer
-
four-domain dimer with a two-stranded beta-sheet arm protruding from one monomer onto the other
homodimer
P66902
crystal structure
homotrimer
-
3 * 48000 (calculated 49100), SDS-PAGE, gelfiltration
monomer
-
1 * 52800, SDS-PAGE
additional information
-
determination of N-terminal amino acid sequence
additional information
-
amino acid analysis
additional information
-
identification of active site amino acids
additional information
-
tertiary structure
Crystallization/COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
crystallographic structure of Arabidopsis thaliana threonine synthase in complex with pyridoxal phosphate and with pyridoxal phosphate and S-adenosylmethionine; hanging drop method, 4C, pH 6.5, resolution of 2.6 A
-
hanging-drop vapour-diffusion method at 293 K. Selenomethionine-substituted apo threonine synthase, 14 Met residues in 58000 Da
-
hanging-drop vapour-diffusion method, crystal structure of apo threonine synthase as solved at 2.25 A resolution from triclinic crystals
-
x-ray diffraction studies
-
refined to 2.5 A. The structure of MtTS has a homodimeric organization in which the two subunits are related by a non-crystallographic 2fold axis. Each subunit is composed of three domains
P66902
sitting-drop vapour-diffusion method, crystal structure at 2.7 A resolution
-
apo-protein and in complex with 2-amino-5-phosphonopentanoic acid and with (E)-4-(3-hydroxy-2-methyl-5-(phosphonooxymethyl)pyridin-4-yl)-2-oxobut-3-enoic acid. The enzyme does not undergo any global conformational change upon the binding of pyridoxal 5'-phosphate. The binding of the substrate analog 2-amino-5-phosphonopentanoic acid to the holoenzyme induces a large conformational change from the open to the closed form in which the small domain moves as a rigid body to close the active site. This closed structure is maintained in the complex with (E)-4-(3-hydroxy-2-methyl-5-(phosphonooxymethyl)pyridin-4-yl)-2-oxobut-3-enoic acid, indicating that threonine synthase is in the closed form in the enamine and the pyridoxal 5'-phosphate-alpha-aminocrotonate aldimine intermediates
Q5SL02
hanging drop vapour diffusion method at 293 K, unligated enzyme form and complex with substrate analogue 2-amino-5-phosphonopentanoic acid, structure determined at 2.15 A and 2.0 A resolution
-
pH STABILITY
pH STABILITY MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
5.2
-
-
inactivation and precipitation below
7
-
P66902
MtTS is inactivated at pH 7 or below
TEMPERATURE STABILITY
TEMPERATURE STABILITY MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
60
-
P66902
MtTS loses less than 10% of the initial activity during a 10 min incubation
GENERAL STABILITY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
bovine serum albumine stabilizes
-
STORAGE STABILITY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
-80C, Na-HEPES buffer, pH 7.5, several months, no loss of activity
-
-80C, MOPS-buffer, pH 7.5, EDTA, dithioerythritol, 2-benzothiazolethiol, glycerol, polyvinylpyrrolidone, several months, no loss of activity
-
-80C, pH 7.8, several months
-
-15C, glycylglycine, several months
-
Purification/COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
native and recombinant enzymes
-
recombinant enzyme
-
Ni2+-affinity chromatography
-
using Ni-NTA chromatography
P66902
partial
-
Cloned/COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
overexpression under the control of the 35S cauliflower mosaic virus promotor in Arabidopsis sp. plants
-
expressed in Escherichia coli
-
expressed in Escherichia coli
-
expressed in Escherichia coli
-
expressed in Nicotiana tabacum
-
expression in transgenic Arabidopsis
-
His-tagged version expressed in Escherichia coli BL21(DE3)
-
expressed as a His-tagged fusion protein
P66902
expressed in Escherichia coli Gif41 (thrC mutant)
-
expression in Escherichia coli
Q5SL02
ENGINEERING
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
additional information
-
Cryptococcus neoformans homoserine and/or threonine biosynthetic genes encoding aspartate kinase (HOM3), homoserine kinase (THR1) and threonine synthase (THR4) are attempted to disrupt. However, each gene proves recalcitrant to disruption, indicating that these genes are essential for Cryptococcus neoformans growth
additional information
P66902
a deletion of the MtTS gene generated a strain of Mycobacterium tuberculosis that requires threonine for growth
APPLICATION
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
agriculture
-
possible herbicide target
agriculture
-
as one of the few enzymes that are cross-activated by the product of another pathway, S-adenosyl-L-methionine, it has a potential application as a target for herbicides
nutrition
-
interesting with respect to attempts to obtain transgenic plants with elevated levels of essential amino acids Met, Lys, Thr
medicine
-
the necessity of homoserine and/or threonine biosynthetic genes encoding aspartate kinase (HOM3), homoserine kinase (THR1) and threonine synthase (THR4) for Cryptococcus neoformans growth, particularly at physiologically relevant temperatures, makes threonine biosynthetic genes ideal anti-cryptococcal drug targets
medicine
-
possibly involved in formation of bacteriocidal antimetabolites