Literature summary for 1.5.1.33 extracted from

Di Pisa, F.; Landi, G.; Dello Iacono, L.; Pozzi, C.; Borsari, C.; Ferrari, S.; Santucci, M.; Santarem, N.; Cordeiro-Da-Silva, A.; Moraes, C.; Alcantara, L.; Fontana, V.; Freitas-Junior, L.; Gul, S.; Kuzikov, M.; Behrens, B.; Poehner, I.; Wade, R.; Costi,
Chroman-4-one derivatives targeting pteridine reductase 1 and showing anti-parasitic activity (2017), Molecules, 22, E426 .

Crystallization (Commentary)

Crystallization (Comment)	Organism
purified enzyme LmPtr1 in ternary complex with compounds 6-hydroxy-2-(3-hydroxyphenyl)-2,3-dihydro-4H-1-benzopyran-4-one and 2-(3,4-dihydroxyphenyl)-6-hydroxy-2,3-dihydro-4H-1-benzopyran-4-one, hanging drop vapour diffusion method, mixing of 0.002 ml of 12.5 mg/ml protein in 20 mM sodium acetate, pH 5.3, containing 1 mM NADPH, and 20 mM DTT, with 0.002 ml of reservoir solution containing 12% PEG 4600, 100 mM sodium acetate buffer pH 5.5 and 120-160 mM calcium acetate, equilibration against reservoir solution, at 20°C, for complex crystals the preformed crystals are soaked in a 2 mM inhibitor solution (dissolved in a 1:1 mixture of 1,4-dioxane and water) for 4.5 h, X-ray diffraction structure determination and analysis at 2.10-2.35 A resolution	Leishmania major
purified enzyme TbPtr1 in ternary complex with compound 6-hydroxy-2-(3-hydroxyphenyl)-2,3-dihydro-4H-1-benzopyran-4-one, sitting drop vapor diffusion method, mixing of equal volumes of protein solution containing 6-10 mg/ml protein in 20 mM Tris-HCl, pH 7.5, and 10 mM DTT, with precipitant solution containing 1.5-2.5 M sodium acetate and 0.1 M sodium citrate, pH 5.0, equilibration against 0.6 ml of reservoir solution, at room temperature, several days, for complexed crystals are soaked in a 2 mM solution of the inhibitor (dissolved in a 1:1 mixture of 1,4-dioxane and water) for 4 h, X-ray diffraction structure determination and analysis at 1.70 A resolution	Trypanosoma brucei

Crystallization (Comment)

Organism

purified enzyme LmPtr1 in ternary complex with compounds 6-hydroxy-2-(3-hydroxyphenyl)-2,3-dihydro-4H-1-benzopyran-4-one and 2-(3,4-dihydroxyphenyl)-6-hydroxy-2,3-dihydro-4H-1-benzopyran-4-one, hanging drop vapour diffusion method, mixing of 0.002 ml of 12.5 mg/ml protein in 20 mM sodium acetate, pH 5.3, containing 1 mM NADPH, and 20 mM DTT, with 0.002 ml of reservoir solution containing 12% PEG 4600, 100 mM sodium acetate buffer pH 5.5 and 120-160 mM calcium acetate, equilibration against reservoir solution, at 20°C, for complex crystals the preformed crystals are soaked in a 2 mM inhibitor solution (dissolved in a 1:1 mixture of 1,4-dioxane and water) for 4.5 h, X-ray diffraction structure determination and analysis at 2.10-2.35 A resolution

Leishmania major

purified enzyme TbPtr1 in ternary complex with compound 6-hydroxy-2-(3-hydroxyphenyl)-2,3-dihydro-4H-1-benzopyran-4-one, sitting drop vapor diffusion method, mixing of equal volumes of protein solution containing 6-10 mg/ml protein in 20 mM Tris-HCl, pH 7.5, and 10 mM DTT, with precipitant solution containing 1.5-2.5 M sodium acetate and 0.1 M sodium citrate, pH 5.0, equilibration against 0.6 ml of reservoir solution, at room temperature, several days, for complexed crystals are soaked in a 2 mM solution of the inhibitor (dissolved in a 1:1 mixture of 1,4-dioxane and water) for 4 h, X-ray diffraction structure determination and analysis at 1.70 A resolution

Trypanosoma brucei

Inhibitors

Inhibitors	Comment	Organism
2-(3,4-dihydroxyphenyl)-3,6-dihydroxy-4H-1-benzopyran-4-one	-	Leishmania major
2-(3,4-dihydroxyphenyl)-3,6-dihydroxy-4H-1-benzopyran-4-one	-	Trypanosoma brucei
2-(3,4-dihydroxyphenyl)-6-hydroxy-2,3-dihydro-4H-1-benzopyran-4-one	-	Leishmania major
2-(3,4-dihydroxyphenyl)-6-hydroxy-2,3-dihydro-4H-1-benzopyran-4-one	-	Trypanosoma brucei
3,6-dihydroxy-2-(3-hydroxyphenyl)-4H-1-benzopyran-4-one	-	Leishmania major
3,6-dihydroxy-2-(3-hydroxyphenyl)-4H-1-benzopyran-4-one	-	Trypanosoma brucei
6-hydroxy-2-(3-hydroxyphenyl)-2,3-dihydro-4H-1-benzopyran-4-one	the compound shows inhibitory activity both against the targeted enzyme and the parasite with a high selectivity and a low toxicity for humans. Only the (R)-isomer binds in the active site, 50% inhibition at 0.05 mM	Leishmania major
6-hydroxy-2-(3-hydroxyphenyl)-2,3-dihydro-4H-1-benzopyran-4-one	the compound shows inhibitory activity both against the targeted enzyme and the parasite with a high selectivity and a low toxicity for humans. Only the (R)-isomer binds in the active site, 81% inhibition at 0.05 mM	Trypanosoma brucei
6-hydroxy-2-(4-hydroxyphenyl)-2,3-dihydro-4H-1-benzopyran-4-one	-	Leishmania major
6-hydroxy-2-(4-hydroxyphenyl)-2,3-dihydro-4H-1-benzopyran-4-one	-	Trypanosoma brucei
additional information	chromen-4-one derivatives as pteridine reductase 1 (PTR1) inhibitors, observed and predicted binding modes of the compounds, docking and modeling, overview. There are differences between the binding modes of the chromen-4-one and the chroman-4-one moiety. No inhibition by 3,6-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one at 0.05 mM. Only the (R)-isomers bind in the active site	Leishmania major
additional information	chromen-4-one derivatives as pteridine reductase 1 (PTR1) inhibitors, observed and predicted binding modes of the compounds, docking and modeling, overview. There are differences between the binding modes of the chromen-4-one and the chroman-4-one moiety. No inhibition by 3,6-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one at 0.05 mM	Trypanosoma brucei
pyrimethamine	complete inhibition at 0.05 mM	Leishmania major
pyrimethamine	complete inhibition at 0.05 mM	Trypanosoma brucei

Natural Substrates/ Products (Substrates)

Natural Substrates	Organism	Comment (Nat. Sub.)	Natural Products	Comment (Nat. Pro.)	Rev.	Reac.
biopterin + 2 NADPH + 2 H+	Trypanosoma brucei	-	5,6,7,8-tetrahydrobiopterin + 2 NADP+	-	?
biopterin + 2 NADPH + 2 H+	Leishmania major	-	5,6,7,8-tetrahydrobiopterin + 2 NADP+	-	?

Organism

Organism	UniProt	Comment	Textmining
Leishmania major	Q01782	-	-
no activity in Homo sapiens	-	-	-
Trypanosoma brucei	O76290	-	-

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.	Reac.
biopterin + 2 NADPH + 2 H+	-	Trypanosoma brucei	5,6,7,8-tetrahydrobiopterin + 2 NADP+	-	?
biopterin + 2 NADPH + 2 H+	-	Leishmania major	5,6,7,8-tetrahydrobiopterin + 2 NADP+	-	?

Subunits

Subunits	Comment	Organism
tetramer	-	Trypanosoma brucei
tetramer	-	Leishmania major

Synonyms

Synonyms	Comment	Organism
LmPTR1	-	Leishmania major
pteridine reductase 1	-	Trypanosoma brucei
pteridine reductase 1	-	Leishmania major
PTR1	-	Trypanosoma brucei
PTR1	-	Leishmania major
TbPTR1	-	Trypanosoma brucei

Temperature Optimum [°C]

Temperature Optimum [°C]	Temperature Optimum Maximum [°C]	Comment	Organism
30	-	assay at	Trypanosoma brucei
30	-	assay at	Leishmania major

pH Optimum

pH Optimum Minimum	pH Optimum Maximum	Comment	Organism
6	-	assay at	Trypanosoma brucei
6	-	assay at	Leishmania major

Cofactor

Cofactor	Comment	Organism	Structure
NADPH	-	Trypanosoma brucei
NADPH	-	Leishmania major

IC50 Value

IC50 Value	IC50 Value Maximum	Comment	Organism	Inhibitor
0.0043	-	pH 6.0, 30°C	Trypanosoma brucei	3,6-dihydroxy-2-(3-hydroxyphenyl)-4H-1-benzopyran-4-one
0.0125	-	pH 6.0, 30°C	Leishmania major	3,6-dihydroxy-2-(3-hydroxyphenyl)-4H-1-benzopyran-4-one
0.031	-	pH 6.0, 30°C	Trypanosoma brucei	6-hydroxy-2-(3-hydroxyphenyl)-2,3-dihydro-4H-1-benzopyran-4-one
0.035	-	pH 6.0, 30°C	Leishmania major	6-hydroxy-2-(4-hydroxyphenyl)-2,3-dihydro-4H-1-benzopyran-4-one
0.035	-	pH 6.0, 30°C	Leishmania major	2-(3,4-dihydroxyphenyl)-3,6-dihydroxy-4H-1-benzopyran-4-one
0.036	-	pH 6.0, 30°C	Leishmania major	2-(3,4-dihydroxyphenyl)-6-hydroxy-2,3-dihydro-4H-1-benzopyran-4-one
0.038	-	pH 6.0, 30°C	Trypanosoma brucei	2-(3,4-dihydroxyphenyl)-3,6-dihydroxy-4H-1-benzopyran-4-one
0.057	-	pH 6.0, 30°C	Leishmania major	6-hydroxy-2-(3-hydroxyphenyl)-2,3-dihydro-4H-1-benzopyran-4-one
0.082	-	pH 6.0, 30°C	Trypanosoma brucei	2-(3,4-dihydroxyphenyl)-6-hydroxy-2,3-dihydro-4H-1-benzopyran-4-one
0.133	-	pH 6.0, 30°C	Trypanosoma brucei	6-hydroxy-2-(4-hydroxyphenyl)-2,3-dihydro-4H-1-benzopyran-4-one

General Information

General Information	Comment	Organism
physiological function	the enzyme is able to reduce both unconjugated and conjugated pterins and provides a metabolic bypass to alleviate a dihydrofolate reductase inhibition	Trypanosoma brucei
physiological function	the enzyme is able to reduce both unconjugated and conjugated pterins and provides a metabolic bypass to alleviate a dihydrofolate reductase inhibition	Leishmania major