Application | Comment | Organism |
---|---|---|
drug development | the enzyme is a target for inhibitor design | Homo sapiens |
Crystallization (Comment) | Organism |
---|---|
two transition-state analogues, by sitting drop vapor diffusion method, 4°C, mixing of 0.002 ml of protein solution, containing native PTPB1, peptide DADEYL, and Na3VO4 in 10 mM Tris, pH 7.5, 25 mM NaCl, 0.2 mM EDTA, and 3 mM DTT, with 0.0005 ml of sucrose 30% v/v solution, and 0.003 ml of precipitant solution, containing 0.1 M HEPES, pH 7.5, 0.2 M magnesium acetate and 15-17% PEG 8000, 3 days, X-ray diffraction structure determination and analysis at 2.25-2.3 A resolution | Homo sapiens |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
vanadate | the equatorial vanadate oxygen atoms bind to the P-loop and assumes a trigonal bipyramidal geometry in both transition state analogue structures, with very similar apical O-O distances, binding structure, overview | Homo sapiens |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.58 | - |
4-nitrophenyl phosphate | pH 5.5, 25°C | Homo sapiens |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Homo sapiens | P18031 | - |
- |
Reaction | Comment | Organism | Reaction ID |
---|---|---|---|
[a protein]-tyrosine phosphate + H2O = [a protein]-tyrosine + phosphate | ping-pong mechanism, catalysis proceeds through a two-step mechanism involving a phosphocysteine intermediate. In the first step, a nucleophilic cysteine thiolate attacks the phosphate ester moiety of the substrate, resulting in formation of a phosphoenzyme intermediate with release of the peptidyl tyrosine. The second step occurs via attack of water on the phosphoenzyme intermediate, and yields the final products inorganic phosphate and the regenerated enzyme. The central binding site for the substrate is the P-loop, a region at the bottom of a pocket that includes the nucleophilic cysteine and backbone amide groups oriented in a horseshoe fashion, catalytic cycle, detailed overview | Homo sapiens |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
4-nitrophenyl phosphate + H2O | - |
Homo sapiens | 4-nitrophenol + phosphate | - |
? | |
additional information | formation and structure of a transition state analogue for the first catalytic step comprising a ternary complex between the catalytic cysteine of PTP1B, vanadate, and the peptide DADEYL, a fragment of a physiological substrate, overview. The equatorial vanadate oxygen atoms bind to the P-loop, and the apical positions are occupied by the peptide tyrosine oxygen and by the PTP1B cysteine sulfur atom. The vanadate assumes a trigonal bipyramidal geometry in both transition state analogue structures, with very similar apical O-O distances, denoting similar transition states for both phosphoryl transfer steps | Homo sapiens | ? | - |
? |
Subunits | Comment | Organism |
---|---|---|
More | PTPB1 possesses a P-loop, a WPD-loop, a Q-loop, a Lys-loop, and a pTyr-recognition loop, that show conformational changes during formation of the transition state | Homo sapiens |
Synonyms | Comment | Organism |
---|---|---|
protein tyrosine phosphatase 1B | - |
Homo sapiens |
PTP1B | - |
Homo sapiens |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
25 | - |
assay at | Homo sapiens |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
24.4 | - |
4-nitrophenyl phosphate | pH 5.5, 25°C | Homo sapiens |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
5.5 | - |
assay at | Homo sapiens |
kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.024 | - |
4-nitrophenyl phosphate | pH 5.5, 25°C | Homo sapiens |