Cloned (Comment) | Organism |
---|---|
recombinant expression of C-terminally His-tagged wild-type and mutant enzymes in Escherichia coli strain BL21 (DE3) | Crassostrea gigas |
recombinant expression of C-terminally His-tagged wild-type and mutant enzymes in Escherichia coli strain BL21 (DE3) | Acropora millepora |
sequence comparisons and phylogenetic tree of serine and aspartate racemases, recombinant expression of C-terminally His-tagged wild-type enzyme in Escherichia coli strain BL21(DE3) | Penaeus monodon |
Protein Variants | Comment | Organism |
---|---|---|
additional information | substituting the triple serine loop region in AspRs enhances serine racemization | Penaeus monodon |
additional information | substituting the triple serine loop region in AspRs enhances serine racemization | Crassostrea gigas |
additional information | substituting the triple serine loop region in AspRs enhances serine racemization | Acropora millepora |
P150S | PCR-based site-directed mutagenesis, the mutant shows reduced aspartate and serine racemase activities compared to the wild-type enzyme | Acropora millepora |
S150P/S151P/S152Y | PCR-based site-directed mutagenesis, the SSS to PPY mutation of Crassostrea AspR triple serine loop region drastically decreases the specific AspR activity to below 0.04% compared to wild-type, whereas it significantly increases the specific SerR and SDH activities by 6-13fold. The large change in the AspR activity in the mutant enzyme is caused by approximately 400fold decrease in kcat rather than by 22-32fold decrease in Km | Crassostrea gigas |
S151P/S152F | PCR-based site-directed mutagenesis, the mutant is inactive as aspartate racemase, but shows serine racemase activity, EC 5.1.1.18 | Acropora millepora |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | kinetics of enzyme AspR with L-Ser and D-Ser as substrates, comparison to the serine racemase enzyme of Penaeus monodon, EC 5.1.1.18, overview | Penaeus monodon | |
additional information | - |
additional information | kinetics of wild-type and mutant enzymes AspR with L-Ser and D-Ser as substrates, comparison to the serine racemase enzyme of Acropora millepora, overview | Acropora millepora | |
additional information | - |
additional information | kinetics of wild-type and mutant enzymes AspR with L-Ser and D-Ser as substrates, comparison to the serine racemase enzyme of Crassostrea gigas, EC 5.1.1.18, overview | Crassostrea gigas | |
1.37 | - |
D-Aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Acropora millepora | |
3.11 | - |
L-aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Acropora millepora | |
3.2 | - |
L-aspartate | recombinant His-tagged mutant P150S, pH 8.0, 30°C | Acropora millepora | |
4.55 | - |
D-Aspartate | recombinant His-tagged mutant P150S, pH 8.0, 30°C | Acropora millepora | |
4.75 | - |
L-aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Crassostrea gigas | |
6.21 | - |
D-Aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Crassostrea gigas | |
9.86 | - |
D-Aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Penaeus monodon | |
14.9 | - |
L-aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Penaeus monodon | |
48.6 | - |
L-aspartate | recombinant His-tagged mutant S150P/S151P/S152Y, pH 8.0, 30°C | Crassostrea gigas | |
80.6 | - |
D-Aspartate | recombinant His-tagged mutant S150P/S151P/S152Y, pH 8.0, 30°C | Crassostrea gigas |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
L-aspartate | Penaeus monodon | - |
D-aspartate | - |
r | |
L-aspartate | Crassostrea gigas | - |
D-aspartate | - |
r | |
L-aspartate | Acropora millepora | - |
D-aspartate | - |
r | |
additional information | Penaeus monodon | the enzyme AspR also shows low serine racemase, SerR (EC 5.1.1.18), activity | ? | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Acropora millepora | JT020910 | - |
- |
Crassostrea gigas | K1QH67 | - |
- |
Penaeus monodon | A0A0U5A554 | - |
- |
Purification (Comment) | Organism |
---|---|
recombinant C-terminally His-tagged wild-type and mutant enzymes from Escherichia coli strain BL21 (DE3) by nickel affinity chromatography | Crassostrea gigas |
recombinant C-terminally His-tagged wild-type and mutant enzymes from Escherichia coli strain BL21 (DE3) by nickel affinity chromatography | Acropora millepora |
recombinant C-terminally His-tagged wild-type enzyme from Escherichia coli strain BL21(DE3) by nickel affinity chromatography | Penaeus monodon |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
D-aspartate | - |
Penaeus monodon | L-aspartate | - |
r | |
D-aspartate | - |
Crassostrea gigas | L-aspartate | - |
r | |
D-aspartate | - |
Acropora millepora | L-aspartate | - |
r | |
L-aspartate | - |
Penaeus monodon | D-aspartate | - |
r | |
L-aspartate | - |
Crassostrea gigas | D-aspartate | - |
r | |
L-aspartate | - |
Acropora millepora | D-aspartate | - |
r | |
additional information | the enzyme AspR also shows low serine racemase, SerR (EC 5.1.1.18), activity | Penaeus monodon | ? | - |
? | |
additional information | the enzyme AspR also shows negligible serine racemase, SerR (EC 5.1.1.18), activity | Crassostrea gigas | ? | - |
? | |
additional information | the enzyme is also active in the racemisation of L- and D-serine, EC 5.1.1.18 | Penaeus monodon | ? | - |
? |
Synonyms | Comment | Organism |
---|---|---|
AspR | - |
Penaeus monodon |
AspR | - |
Crassostrea gigas |
AspR | - |
Acropora millepora |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
30 | - |
assay at | Penaeus monodon |
30 | - |
assay at | Crassostrea gigas |
30 | - |
assay at | Acropora millepora |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.0228 | - |
L-aspartate | recombinant His-tagged mutant S150P/S151P/S152Y, pH 8.0, 30°C | Crassostrea gigas | |
0.0322 | - |
D-Aspartate | recombinant His-tagged mutant S150P/S151P/S152Y, pH 8.0, 30°C | Crassostrea gigas | |
8.65 | - |
L-aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Crassostrea gigas | |
13.1 | - |
D-Aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Crassostrea gigas | |
14.5 | - |
L-aspartate | recombinant His-tagged mutant P150S, pH 8.0, 30°C | Acropora millepora | |
17.8 | - |
D-Aspartate | recombinant His-tagged mutant P150S, pH 8.0, 30°C | Acropora millepora | |
25.3 | - |
D-Aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Acropora millepora | |
27.6 | - |
D-Aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Penaeus monodon | |
33 | - |
L-aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Penaeus monodon | |
57.7 | - |
L-aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Acropora millepora |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
8 | - |
assay at | Penaeus monodon |
8 | - |
assay at | Crassostrea gigas |
8 | - |
assay at | Acropora millepora |
General Information | Comment | Organism |
---|---|---|
evolution | the enzyme belongs to the serine/aspartate racemase family, the triple serine loop region regulates the aspartate racemase activity of the serine/aspartate racemase family members. The ancestral gene of the serine/aspartate racemase family is SerR, the evolution of AspR from SerR occured in three steps: first, gene duplication of the original SerR gene. Second, introduction of the two serine residues at position 151 and 152, resulting in a drastic increase of the AspR activity, and third, formation of the complete triple serine loop region by additional introduction of serine residue at position 150, resulting in enhanced the enzyme specificity for aspartate | Penaeus monodon |
evolution | the enzyme belongs to the serine/aspartate racemase family, the triple serine loop region regulates the aspartate racemase activity of the serine/aspartate racemase family members. The ancestral gene of the serine/aspartate racemase family is SerR, the evolution of AspR from SerR occured in three steps: first, gene duplication of the original SerR gene. Second, introduction of the two serine residues at position 151 and 152, resulting in a drastic increase of the AspR activity, and third, formation of the complete triple serine loop region by additional introduction of serine residue at position 150, resulting in enhanced the enzyme specificity for aspartate | Crassostrea gigas |
evolution | the enzyme belongs to the serine/aspartate racemase family, the triple serine loop region regulates the aspartate racemase activity of the serine/aspartate racemase family members. The ancestral gene of the serine/aspartate racemase family is SerR, the evolution of AspR from SerR occured in three steps: first, gene duplication of the original SerR gene. Second, introduction of the two serine residues at position 151 and 152, resulting in a drastic increase of the AspR activity, and third, formation of the complete triple serine loop region by additional introduction of serine residue at position 150, resulting in enhanced the enzyme specificity for aspartate | Acropora millepora |
malfunction | substituting the triple serine loop region in AspRs enhances serine racemization | Penaeus monodon |
malfunction | substituting the triple serine loop region in AspRs enhances serine racemization. Single amino acid substitution mutants, H150S, P151S and N152S, reveal several effects on activity. The Ser150 substitution decreases all enzyme activities, especially the serine dehydrogenase (SDH) activity, while Ser151 dramatically increases the SerR and AspR activities with no change on SDH activity. An increase in the AspR activity is observed after introducing Ser152, while there is little or no change in the other activities | Crassostrea gigas |
malfunction | substituting the triple serine loop region in AspRs enhances serine racemization. Single amino acid substitution mutants, H150S, P151S and N152S, reveal several effects on activity. The Ser150 substitution decreases all enzyme activities, especially the serine dehydrogenase (SDH) activity, while Ser151 dramatically increases the SerR and AspR activities with no change on SDH activity. An increase in the AspR activity is observed after introducing Ser152, while there is little or no change in the other activities | Acropora millepora |
additional information | important role of triple serine loop region for the aspratate racemase activity in several SerRs and AspRs, structure-function analysis, overview | Penaeus monodon |
additional information | important role of triple serine loop region for the aspratate racemase activity in several SerRs and AspRs, structure-function analysis, overview | Crassostrea gigas |
additional information | important role of triple serine loop region for the aspratate racemase activity in several SerRs and AspRs, structure-function analysis, overview | Acropora millepora |
kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.0004 | - |
D-Aspartate | recombinant His-tagged mutant S150P/S151P/S152Y, pH 8.0, 30°C | Crassostrea gigas | |
0.0005 | - |
L-aspartate | recombinant His-tagged mutant S150P/S151P/S152Y, pH 8.0, 30°C | Crassostrea gigas | |
1.82 | - |
L-aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Crassostrea gigas | |
2.12 | - |
D-Aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Crassostrea gigas | |
2.22 | - |
L-aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Penaeus monodon | |
2.8 | - |
D-Aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Penaeus monodon | |
3.9 | - |
D-Aspartate | recombinant His-tagged mutant P150S, pH 8.0, 30°C | Acropora millepora | |
4.7 | - |
L-aspartate | recombinant His-tagged mutant P150S, pH 8.0, 30°C | Acropora millepora | |
18.4 | - |
D-Aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Acropora millepora | |
18.7 | - |
L-aspartate | recombinant His-tagged wild-type enzyme, pH 8.0, 30°C | Acropora millepora |