Application | Comment | Organism |
---|---|---|
drug development | the absence of an LdASNA homologue from humans and its essentiality for the parasites make LdASNA a drug target | Leishmania donovani |
Cloned (Comment) | Organism |
---|---|
gene LDBPK_300470, DNA and amino acid sequence determination and analysis, sequence comaparisons and phylogenetic analysis, cloning of the pSP-alpha-blast-alpha-ASNA and pSP72-alpha-neo-alpha-GFP-ASNA episome, overexpression of GFP-tagged ASNA in Leishmania donovani Bob strain MHOM/SD/62/1SCL2D, recombinant expression of N-terminally His6-tagged enzyme in Escherichia coli strain BL21 | Leishmania donovani |
Protein Variants | Comment | Organism |
---|---|---|
additional information | gene deletion mutations of gene asnA are attempted via targeted gene replacement. Gene deletion of LdASNA leads to growth delay in mutants. Chromosomal null mutants of LdASNA cannot be obtained as the double transfectant mutants show aneuploidy | Leishmania donovani |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.6 | - |
L-aspartate | recombinant enzyme, pH 7.8, 37°C | Leishmania donovani | |
1.2 | - |
ATP | recombinant enzyme, pH 7.8, 37°C | Leishmania donovani | |
5.95 | - |
NH3 | recombinant enzyme, pH 7.8, 37°C | Leishmania donovani | |
10.3 | - |
L-glutamine | recombinant enzyme, pH 7.8, 37°C | Leishmania donovani |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
cytosol | - |
Leishmania donovani | 5829 | - |
mitochondrion | - |
Leishmania donovani | 5739 | - |
additional information | subcellular localization study using GFP-tagged enzyme | Leishmania donovani | - |
- |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | required | Leishmania donovani |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + L-aspartate + L-glutamine + H2O | Leishmania donovani | - |
AMP + diphosphate + L-asparagine + L-glutamate | - |
? | |
ATP + L-aspartate + L-glutamine + H2O | Leishmania donovani BPK282A1 | - |
AMP + diphosphate + L-asparagine + L-glutamate | - |
? | |
ATP + L-aspartate + NH3 | Leishmania donovani | also reaction of EC 6.3.1.1 | AMP + diphosphate + L-asparagine | - |
? | |
ATP + L-aspartate + NH3 | Leishmania donovani BPK282A1 | also reaction of EC 6.3.1.1 | AMP + diphosphate + L-asparagine | - |
? | |
L-glutamine + H2O | Leishmania donovani | - |
L-glutamate + NH3 | - |
? | |
L-glutamine + H2O | Leishmania donovani BPK282A1 | - |
L-glutamate + NH3 | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Leishmania donovani | E9BLE1 | - |
- |
Leishmania donovani BPK282A1 | E9BLE1 | - |
- |
Purification (Comment) | Organism |
---|---|
recombinant His6-tagged enzyme from Escherichia coli strain BL21 by nickel affinity chromatography to over 95% purity | Leishmania donovani |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
kinetoplastid | - |
Leishmania donovani | - |
promastigote | - |
Leishmania donovani | - |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
0.0696 | - |
purified recombinant enzyme, pH 7.8, 37°C, substrate L-asparate | Leishmania donovani |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + L-aspartate + L-glutamine + H2O | - |
Leishmania donovani | AMP + diphosphate + L-asparagine + L-glutamate | - |
? | |
ATP + L-aspartate + L-glutamine + H2O | - |
Leishmania donovani BPK282A1 | AMP + diphosphate + L-asparagine + L-glutamate | - |
? | |
ATP + L-aspartate + NH3 | also reaction of EC 6.3.1.1 | Leishmania donovani | AMP + diphosphate + L-asparagine | - |
? | |
ATP + L-aspartate + NH3 | also reaction of EC 6.3.1.1 | Leishmania donovani BPK282A1 | AMP + diphosphate + L-asparagine | - |
? | |
L-glutamine + H2O | - |
Leishmania donovani | L-glutamate + NH3 | - |
? | |
L-glutamine + H2O | - |
Leishmania donovani BPK282A1 | L-glutamate + NH3 | - |
? | |
additional information | asparagine is formed in two steps: the beta-carboxylate group of aspartate is first activated by ATP to form an aminoacyl-AMP before its amidation by a nucleophilic attack with an ammonium ion. LdASNA is active and preferentially utilizes ammonia, although it is also capable of utilizing glutamine as a nitrogen source | Leishmania donovani | ? | - |
? | |
additional information | asparagine is formed in two steps: the beta-carboxylate group of aspartate is first activated by ATP to form an aminoacyl-AMP before its amidation by a nucleophilic attack with an ammonium ion. LdASNA is active and preferentially utilizes ammonia, although it is also capable of utilizing glutamine as a nitrogen source | Leishmania donovani BPK282A1 | ? | - |
? |
Subunits | Comment | Organism |
---|---|---|
? | x * 40000, about, sequence calculation, x * 44000, recombinant Hi6-tagged enzyme, SDS-PAGE | Leishmania donovani |
Synonyms | Comment | Organism |
---|---|---|
AsnA | - |
Leishmania donovani |
Asparagine synthetase A | - |
Leishmania donovani |
bacterial type asparagine synthetase A | - |
Leishmania donovani |
LDBPK_300470 | - |
Leishmania donovani |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
37 | - |
assay at | Leishmania donovani |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.8 | - |
assay at | Leishmania donovani |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
ATP | - |
Leishmania donovani |
Organism | Comment | pI Value Maximum | pI Value |
---|---|---|---|
Leishmania donovani | sequence calculation | - |
5.4 |
General Information | Comment | Organism |
---|---|---|
metabolism | asparagine is formed by two structurally distinct asparagine synthetases in prokaryotes. One is the ammonia-utilizing asparagine synthetase A (AsnA, EC 6.3.1.1), and the other is asparagine synthetase B (AsnB, EC 6.3.5.4) that uses glutamine or ammonia as a nitrogen source. Sequence-based analysis suggests that Leishmania spp. possess the asparagine tRNA synthetase paralogue asparagine synthetase A (LdASNA) that is ammonia-dependent, but enzyme LdASNA from Leishmania donovani is both ammonia- and glutamine-dependent, EC 6.3.5.4 | Leishmania donovani |
physiological function | enzyme LdASNA is essential for survival of the Leishmania parasite | Leishmania donovani |