Cloned (Comment) | Organism |
---|---|
gene PTR1, recombinant expression of His-tagged enzyme in Escherichia coli | Trypanosoma brucei brucei |
Crystallization (Comment) | Organism |
---|---|
purified recombinant His-tagged TbPTR1, hanging drop vapour diffusion method, a few days at room temperature. Well-ordered monoclinic crystals are obtained using a precipitant solution composed of 2.0-2.5 M sodium acetate and 0.1 M sodium citrate, pH 5.0, the complex with PYR is obtained by the soaking technique, adding 3 mM of the compound (solubilized in DMSO) in crystallization drops containing preformed TbPTR1 crystals (without exceeding a DMSO/crystal solution ratio of 1:9) and incubating them overnight at room temperature, molecular replacement using a functional enzyme tetramer (PDB ID 6TBX) as searching model, and modelling | Trypanosoma brucei brucei |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
1-(3,4-dichlorophenyl)-6,6-dimethyl-1,6-dihydro-1,3,5-triazine-2,4-diamine | competitive inhibition | Trypanosoma brucei brucei | |
1-(3,4-dichlorophenyl)-6-(4-nitrophenyl)-1,6-dihydro-1,3,5-triazine-2,4-diamine | competitive inhibition | Trypanosoma brucei brucei | |
1-(4-chlorophenyl)-6-methyl-1,6-dihydro-1,3,5-triazine-2,4-diamine | competitive inhibition | Trypanosoma brucei brucei | |
1-(4-chlorophenyl)-6-propyl-1,6-dihydro-1,3,5-triazine-2,4-diamine | competitive inhibition | Trypanosoma brucei brucei | |
1-(4-methoxyphenyl)-6,6-dimethyl-1,6-dihydro-1,3,5-triazine-2,4-diamine | competitive inhibition | Trypanosoma brucei brucei | |
4-(4,6-diamino-2,2-dimethyl-1,3,5-triazin-1(2H)-yl)phenol | competitive inhibition | Trypanosoma brucei brucei | |
5-(4-chlorophenyl)-1,3,5-triazaspiro[5.5]undeca-1,3-diene-2,4-diamine | competitive inhibition | Trypanosoma brucei brucei | |
cycloguanil | CYC, the known inhibitor of Plasmodial and Trypanosomal DHFR-TS enzymes is also as an inhibitor of TbPTR1 | Trypanosoma brucei brucei | |
methotrexate | MTX | Trypanosoma brucei brucei | |
additional information | comparison of the X-ray crystal structure of the TbPTR1:NADP(H):CYC complex (PDB ID 6HNC) with the derivatives' structures 1-(3,4-dichlorophenyl)-6,6-dimethyl-1,6-dihydro-1,3,5-triazine-2,4-diamine (PDB ID 6HNR) and 1-(3,4-dichlorophenyl)-6-(4-nitrophenyl)-1,6-dihydro-1,3,5-triazine-2,4-diamine (PDB ID 6HOW). Selectivity of the ihibitors versus enzymes PTR1 and DHFR, overview | Trypanosoma brucei brucei | |
N-[6-amino-5-(4-methoxyphenyl)-4,4-dimethyl-4,5-dihydrotriazin-2-yl]acetamide | competitive inhibition | Trypanosoma brucei brucei | |
pyrimethamine | PYR | Trypanosoma brucei brucei |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | kinetics by non-tight binding Michaelis-Menten model | Trypanosoma brucei brucei |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
7,8-dihydrobiopterin + NADPH + H+ | Trypanosoma brucei brucei | - |
5,6,7,8-tetrahydrobiopterin + NADP+ | - |
? | |
7,8-dihydrofolate + NADPH + H+ | Trypanosoma brucei brucei | - |
5,6,7,8-tetrahydrofolate + NADP+ | - |
? | |
biopterin + NADPH + H+ | Trypanosoma brucei brucei | - |
7,8-dihydrobiopterin + NADP+ | - |
? | |
folate + NADPH + H+ | Trypanosoma brucei brucei | reaction of EC 1.5.1.3 | 7,8-dihydrofolate + NADP+ | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Trypanosoma brucei brucei | O76290 | - |
- |
Purification (Comment) | Organism |
---|---|
recombinant His-tagged enzyme from Escherichia coli | Trypanosoma brucei brucei |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
7,8-dihydrobiopterin + NADPH + H+ | - |
Trypanosoma brucei brucei | 5,6,7,8-tetrahydrobiopterin + NADP+ | - |
? | |
7,8-dihydrofolate + NADPH + H+ | - |
Trypanosoma brucei brucei | 5,6,7,8-tetrahydrofolate + NADP+ | - |
? | |
biopterin + NADPH + H+ | - |
Trypanosoma brucei brucei | 7,8-dihydrobiopterin + NADP+ | - |
? | |
folate + NADPH + H+ | reaction of EC 1.5.1.3 | Trypanosoma brucei brucei | 7,8-dihydrofolate + NADP+ | - |
? |
Synonyms | Comment | Organism |
---|---|---|
More | cf. EC 1.5.1.3 | Trypanosoma brucei brucei |
pteridine reductase 1 | - |
Trypanosoma brucei brucei |
PTR1 | - |
Trypanosoma brucei brucei |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
22 | - |
assay at room temperature | Trypanosoma brucei brucei |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
3.7 | - |
assay at | Trypanosoma brucei brucei |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
NADPH | - |
Trypanosoma brucei brucei |
Ki Value [mM] | Ki Value maximum [mM] | Inhibitor | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | all the investigated molecules are assumed to act as full competitive inhibitor and analysed according to the non-tight binding Michaelis-Menten model | Trypanosoma brucei brucei |
IC50 Value | IC50 Value Maximum | Comment | Organism | Inhibitor | Structure |
---|---|---|---|---|---|
0.00009 | - |
pH 3.7, 22°C | Trypanosoma brucei brucei | pyrimethamine | |
0.000186 | - |
pH 3.7, 22°C, recombinant enzyme | Trypanosoma brucei brucei | 1-(3,4-dichlorophenyl)-6-(4-nitrophenyl)-1,6-dihydro-1,3,5-triazine-2,4-diamine | |
0.00067 | - |
pH 3.7, 22°C, recombinant enzyme | Trypanosoma brucei brucei | 1-(4-methoxyphenyl)-6,6-dimethyl-1,6-dihydro-1,3,5-triazine-2,4-diamine | |
0.000692 | - |
pH 3.7, 22°C, recombinant enzyme | Trypanosoma brucei brucei | 1-(3,4-dichlorophenyl)-6,6-dimethyl-1,6-dihydro-1,3,5-triazine-2,4-diamine | |
0.000793 | - |
pH 3.7, 22°C | Trypanosoma brucei brucei | methotrexate | |
0.00083 | - |
pH 3.7, 22°C, recombinant enzyme | Trypanosoma brucei brucei | N-[6-amino-5-(4-methoxyphenyl)-4,4-dimethyl-4,5-dihydrotriazin-2-yl]acetamide | |
0.00122 | - |
pH 3.7, 22°C, recombinant enzyme | Trypanosoma brucei brucei | 5-(4-chlorophenyl)-1,3,5-triazaspiro[5.5]undeca-1,3-diene-2,4-diamine | |
0.0041 | - |
pH 3.7, 22°C, recombinant enzyme | Trypanosoma brucei brucei | 4-(4,6-diamino-2,2-dimethyl-1,3,5-triazin-1(2H)-yl)phenol | |
0.00602 | - |
pH 3.7, 22°C, recombinant enzyme | Trypanosoma brucei brucei | 1-(4-chlorophenyl)-6-methyl-1,6-dihydro-1,3,5-triazine-2,4-diamine | |
0.0275 | - |
pH 3.7, 22°C, recombinant enzyme | Trypanosoma brucei brucei | 1-(4-chlorophenyl)-6-propyl-1,6-dihydro-1,3,5-triazine-2,4-diamine | |
0.0316 | - |
pH 3.7, 22°C | Trypanosoma brucei brucei | cycloguanil |
Organism | Comment | Expression |
---|---|---|
Trypanosoma brucei brucei | under dihydrofolate reductase (DHFR, EC 1.5.1.3) inhibition, the gene is upregulated, providing reduced folates necessary for parasite survival | up |
General Information | Comment | Organism |
---|---|---|
evolution | PTR1 is a NADPH-dependent enzyme belonging to the short-chain dehydrogenase/reductase (SDR) family | Trypanosoma brucei brucei |
metabolism | traditional antifolates, such as methotrexate (MTX) inhibiting DHFR, are poorly effective towards trypanosome parasites because of the metabolic bypass provided by PTR1 also catalyzing folate reduction in addition to the conversion of biopterin to 7,8-dihydrobiopterin (DHB) and subsequently to 5,6,7,8-tetrahydrobiopterin (THB) | Trypanosoma brucei brucei |
physiological function | in addition to folate reduction, PTR1 also catalyzes the conversion of biopterin to 7,8-dihydrobiopterin (DHB) and subsequently to 5,6,7,8-tetrahydrobiopterin (THB). Under dihydrofolate reductase (DHFR, EC 1.5.1.3) inhibition, PTR1 is upregulated providing reduced folates necessary for parasite survival | Trypanosoma brucei brucei |