Cloned (Comment) | Organism |
---|---|
expressed in Escherichia coli BL21 cells | Leishmania donovani |
gene Tb927.6.1880, recombinant expression of N-terminally His6-tagged enzyme in Escherichia coli strain BL21 | Trypanosoma brucei brucei |
Crystallization (Comment) | Organism |
---|---|
purified recombinant His6-tagged apoenzyme, hanging drop vapor diffusion method, mixing of 0.001 ml of 73 mg/ml protein in 50 mM Tris-Cl, 200 mM NaCl, and 10 mM 2-mercaptoethanol, pH 7.5, with 0.001 ml of reservoir solution containing 0% w/v PEG 20000, 20% v/v PEG monomethyl ether 550, 0.03 M NPS (sodium nitrate, disodium hydrogen phosphate, ammonium sulfate), and 0.1 M MOPS/HEPES-Na, pH 7.5, 20°C, X-ray diffraction structure determination and analysis at 2.2 A resolution, modeling | Trypanosoma brucei brucei |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.6 | - |
L-aspartate | at pH 7.8 and 37°C | Leishmania donovani | |
1.2 | - |
L-aspartate | at pH 7.8 and 37°C | Leishmania donovani | |
5.95 | - |
NH3 | at pH 7.8 and 37°C | Leishmania donovani | |
10.3 | - |
glutamine | at pH 7.8 and 37°C | Leishmania donovani |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
cytoplasm | - |
Leishmania donovani | 5737 | - |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | required | Trypanosoma brucei brucei |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + L-aspartate + NH3 | Leishmania donovani | - |
AMP + diphosphate + L-asparagine | - |
? | |
ATP + L-aspartate + NH3 | Leishmania donovani Bob | - |
AMP + diphosphate + L-asparagine | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Leishmania donovani | - |
- |
- |
Leishmania donovani Bob | - |
- |
- |
Trypanosoma brucei brucei | Q57WT9 | - |
- |
Trypanosoma brucei brucei 927/4 GUTat10.1 | Q57WT9 | - |
- |
Purification (Comment) | Organism |
---|---|
recombinant His6-tagged enzyme from Escherichia coli strain BL21 by nickel affinity chromatography to over 95% purity, followed by gel filtration | Trypanosoma brucei brucei |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
kinetoplastid | - |
Trypanosoma brucei brucei | - |
promastigote | - |
Leishmania donovani | - |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + L-aspartate + glutamine | - |
Leishmania donovani | ? | - |
? | |
ATP + L-aspartate + glutamine | - |
Leishmania donovani Bob | ? | - |
? | |
ATP + L-aspartate + NH3 | - |
Leishmania donovani | AMP + diphosphate + L-asparagine | - |
? | |
ATP + L-aspartate + NH3 | - |
Leishmania donovani Bob | AMP + diphosphate + L-asparagine | - |
? |
Subunits | Comment | Organism |
---|---|---|
? | x * 40000, calculated from amino acid sequence | Leishmania donovani |
? | x * 40000, His6-tagged enzyme, SDS-PAGE | Leishmania donovani |
Synonyms | Comment | Organism |
---|---|---|
AsnA | - |
Leishmania donovani |
AsnA | - |
Trypanosoma brucei brucei |
Asparagine synthetase A | - |
Leishmania donovani |
Asparagine synthetase A | - |
Trypanosoma brucei brucei |
Tb927.6.1880 | - |
Trypanosoma brucei brucei |
TbASNA | - |
Trypanosoma brucei brucei |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
ATP | - |
Leishmania donovani | |
ATP | - |
Trypanosoma brucei brucei |
Organism | Comment | pI Value Maximum | pI Value |
---|---|---|---|
Leishmania donovani | calculated from amino acid sequence | - |
5.4 |
General Information | Comment | Organism |
---|---|---|
evolution | existence of a very significant conservation in active site residues between TbASNA and Escherichia coli AsnA. Asparagine synthetase is an enzyme that catalyzes the synthesis of asparagine from aspartate using ATP as the energy source in the presence of a nitrogen donor. The nitrogen donor can be glutamine or ammonia. Two families of asparagine synthetases are known to date: One is asparagine synthetase A (AsnA), which utilizes nitrogen only from an ammonia source reported from prokaryotes as well as from archaea. The other family is asparagine synthetase B (AsnB) whose members are found in prokaryotes and eukaryotes. Members of the AsnB family preferentially utilize glutamine as the nitrogen source, although they are capable of utilizing both glutamine and ammonia. Although they are eukaryotes, Leishmania and Trypanosoma surprisingly possess both ASNA and ASNB | Trypanosoma brucei brucei |
physiological function | the enzyme is essential for survival of the Leishmania parasite | Leishmania donovani |