Cloned (Comment) | Organism |
---|---|
recombinant expression of wild-type and mutant enzymes | Homo sapiens |
recombinant expression of wild-type and mutant enzymes | Escherichia coli |
recombinant expression of wild-type and mutant enzymes | Mesomycoplasma mobile |
recombinant expression of wild-type and mutant enzymes | Aquifex aeolicus |
recombinant expression of wild-type and mutant enzymes | Pyrococcus horikoshii |
Protein Variants | Comment | Organism |
---|---|---|
K452A | site-directed mutagenesis, the mutation has only a minimal effect on aminoacylation activity, the Km values is not significantly altered compared to wild-type | Mesomycoplasma mobile |
K452E | site-directed mutagenesis, the mutation has only a minimal effect on aminoacylation activity, the Km values is not significantly altered compared to wild-type | Mesomycoplasma mobile |
K671A | site-directed mutagenesis, the mutation does no affect the catalytic efificiency | Escherichia coli |
K692A | site-directed mutagenesis, the mutation has no effect on tRNA charging activity | Pyrococcus horikoshii |
K696A | site-directed mutagenesis, the mutant shows a highly reduced kcat value compared to wild-type, while the Km value is 3fold increased | Pyrococcus horikoshii |
K699A | site-directed mutagenesis, the mutation has no effect on tRNA charging activity | Pyrococcus horikoshii |
additional information | a helix alpha3-deletion mutant is inactive | Escherichia coli |
R456A | site-directed mutagenesis, 75% reduced catalytic efficiency compared to wild-type, the Km values is not significantly altered | Mesomycoplasma mobile |
R456E | site-directed mutagenesis, 79% reduced catalytic efficiency compared to wild-type, the Km values is not significantly altered | Mesomycoplasma mobile |
R668A | site-directed mutagenesis, the mutant shows 77% reduced catalytic efficiency compared to wild-type, the rate of AMP formation is decreased compared to the wild-type | Escherichia coli |
R668A/R672A | site-directed mutagenesis, the mutant shows 93.6% reduced catalytic efficiency compared to wild-type, the rate of AMP formation is decreased compared to the wild-type | Escherichia coli |
R668E | site-directed mutagenesis, the mutant shows 95% reduced catalytic efficiency compared to wild-type, the rate of AMP formation is decreased compared to the wild-type | Escherichia coli |
R668E/R672E | site-directed mutagenesis, the mutant shows 98.6% reduced catalytic efficiency compared to wild-type. But the almost inactive mutant exhibits intact Leu activation activity comparable with the wild-type enzyme | Escherichia coli |
R672A | site-directed mutagenesis, the rate of AMP formation is decreased compared to the wild-type | Escherichia coli |
R672E | site-directed mutagenesis, the rate of AMP formation is decreased compared to the wild-type | Escherichia coli |
R698A | site-directed mutagenesis, the mutation has no effect on tRNA charging activity | Pyrococcus horikoshii |
R703A | site-directed mutagenesis, kcat of mutant PhLeuRSR703A is much lower than that of wild-type PhLeuRS | Pyrococcus horikoshii |
R766A | site-directed mutagenesis, the mutation decreases the kcat/Km value to less than 10% that of the wild-type enzyme hcLeuRS | Homo sapiens |
R94A | site-directed mutagenesis, mutating Arg94 to Ala decreases kcat/Km values to 34% of that of wild-type AaLeuRS | Aquifex aeolicus |
R94A/R98A | site-directed mutagenesis, 83% reduced catalytic efficiency compared to wild-type | Aquifex aeolicus |
R94E | site-directed mutagenesis, mutating Arg94 to Glu decreases kcat/Km values to 22% of that of wild-type AaLeuRS | Aquifex aeolicus |
R94E/R98E | site-directed mutagenesis, the rate of AMP formation is decreased compared to the wild-type | Aquifex aeolicus |
R98A | site-directed mutagenesis, the mutation does not alter the catalytic efficiency | Aquifex aeolicus |
R98E | site-directed mutagenesis, the rate of AMP formation is decreased compared to the wild-type | Aquifex aeolicus |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | dissociation constants of LeuRS and mutants from Escherichia coli for their cognate tRNAs. Reaction kinetics of EcLeuRS for Mycoplasma mobile MmtRNAUAALeu and mutant variants, kinetic constants of EcLeuRS, chimeric LeuRS and their mutants for tRNALeu in aminoacylation reaction and for AMP formation in the presence of Nva and MmtRNACAA, detailed overview | Escherichia coli | |
additional information | - |
additional information | dissociation constants of LeuRS and mutants from human cytoplasm for their cognate tRNAs | Homo sapiens | |
0.00012 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant mutant R703A | Pyrococcus horikoshii | |
0.0003 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant wild-type enzyme | Aquifex aeolicus | |
0.00031 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R98A | Aquifex aeolicus | |
0.00039 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R98E | Aquifex aeolicus | |
0.00044 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant mutant K692A | Pyrococcus horikoshii | |
0.00052 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant mutant K698A | Pyrococcus horikoshii | |
0.0006 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant mutant K699A | Pyrococcus horikoshii | |
0.00065 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant mutant K696A | Pyrococcus horikoshii | |
0.00074 | - |
tRNACAGLeu | pH 7.8, 37°C, recombinant wild-type enzyme | Homo sapiens | |
0.00075 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R94A | Aquifex aeolicus | |
0.00081 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R94A/R98A | Aquifex aeolicus | |
0.00081 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R94E | Aquifex aeolicus | |
0.00088 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R94E/R98E | Aquifex aeolicus | |
0.0015 | - |
tRNAUAALeu | pH 7.8, 30°C, recombinant wild-type enzyme | Mesomycoplasma mobile | |
0.0016 | - |
tRNAUAALeu | pH 7.5, 37°C, recombinant wild-type enzyme | Escherichia coli | |
0.0017 | - |
tRNAUAALeu | pH 7.8, 30°C, recombinant mutant K452A | Mesomycoplasma mobile | |
0.0017 | - |
tRNACAGLeu | pH 7.8, 37°C, recombinant mutant R668A | Homo sapiens | |
0.0019 | - |
tRNAUAALeu | pH 7.8, 30°C, recombinant mutant K452E | Mesomycoplasma mobile | |
0.002 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant wild-type enzyme | Pyrococcus horikoshii | |
0.0022 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant wild-type enzyme | Escherichia coli | |
0.0022 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R668A/R672A | Escherichia coli | |
0.0023 | - |
tRNAUAALeu | pH 7.8, 30°C, recombinant mutant K456A | Mesomycoplasma mobile | |
0.0024 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant K671A | Escherichia coli | |
0.0024 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R672A | Escherichia coli | |
0.0025 | - |
tRNAUAALeu | pH 7.8, 30°C, recombinant mutant K456E | Mesomycoplasma mobile | |
0.0028 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R668A | Escherichia coli | |
0.0028 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R672E | Escherichia coli | |
0.0054 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R668E | Escherichia coli | |
0.0058 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R668E/R672E | Escherichia coli |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
cytoplasm | - |
Homo sapiens | 5737 | - |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | required | Homo sapiens | |
Mg2+ | required | Escherichia coli | |
Mg2+ | required | Mesomycoplasma mobile | |
Mg2+ | required | Aquifex aeolicus | |
Mg2+ | required | Pyrococcus horikoshii |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + L-leucine + tRNALeu | Homo sapiens | - |
AMP + diphosphate + L-leucyl-tRNALeu | - |
? | |
ATP + L-leucine + tRNALeu | Escherichia coli | - |
AMP + diphosphate + L-leucyl-tRNALeu | - |
? | |
ATP + L-leucine + tRNALeu | Mesomycoplasma mobile | - |
AMP + diphosphate + L-leucyl-tRNALeu | - |
? | |
ATP + L-leucine + tRNALeu | Aquifex aeolicus | - |
AMP + diphosphate + L-leucyl-tRNALeu | - |
? | |
ATP + L-leucine + tRNALeu | Pyrococcus horikoshii | - |
AMP + diphosphate + L-leucyl-tRNALeu | - |
? | |
ATP + L-leucine + tRNALeu | Mesomycoplasma mobile ATCC 43663 / 163K / NCTC 11711 | - |
AMP + diphosphate + L-leucyl-tRNALeu | - |
? | |
ATP + L-leucine + tRNALeu | Pyrococcus horikoshii ATCC 700860 / DSM 12428 / JCM 9974 / NBRC 100139 / OT-3 | - |
AMP + diphosphate + L-leucyl-tRNALeu | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Aquifex aeolicus | O66680 AND O67646 | alpha- and beta-subunit | - |
Escherichia coli | P07813 | - |
- |
Homo sapiens | Q9P2J5 | - |
- |
Mesomycoplasma mobile | Q6KHA5 | - |
- |
Mesomycoplasma mobile ATCC 43663 / 163K / NCTC 11711 | Q6KHA5 | - |
- |
Pyrococcus horikoshii | O58698 | - |
- |
Pyrococcus horikoshii ATCC 700860 / DSM 12428 / JCM 9974 / NBRC 100139 / OT-3 | O58698 | - |
- |
Purification (Comment) | Organism |
---|---|
recombinant wild-type and mutant enzymes | Homo sapiens |
recombinant wild-type and mutant enzymes | Escherichia coli |
recombinant wild-type and mutant enzymes | Mesomycoplasma mobile |
recombinant wild-type and mutant enzymes | Aquifex aeolicus |
recombinant wild-type and mutant enzymes | Pyrococcus horikoshii |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + L-leucine + tRNACAALeu | Mycoplasma mobile tRNACAALeu (MmtRNACAALeu) and mutat derivatives | Mesomycoplasma mobile | AMP + diphosphate + L-leucyl-tRNAUAALeu | - |
? | |
ATP + L-leucine + tRNACAALeu | Mycoplasma mobile tRNACAALeu (MmtRNACAALeu) and mutat derivatives | Mesomycoplasma mobile ATCC 43663 / 163K / NCTC 11711 | AMP + diphosphate + L-leucyl-tRNAUAALeu | - |
? | |
ATP + L-leucine + tRNACAGLeu | human cytoplasmic tRNACAGLeu (hctRNACAG) | Homo sapiens | AMP + diphosphate + L-leucyl-tRNACAGLeu | - |
? | |
ATP + L-leucine + tRNAGAGLeu | Aquifex aeolicus tRNAGAGLeu (AatRNAGAGLeu) | Aquifex aeolicus | AMP + diphosphate + L-leucyl-tRNAGAGLeu | - |
? | |
ATP + L-leucine + tRNAGAGLeu | Escherichia coli tRNAGAGLeu (Ect-RNAGAGLeu) | Escherichia coli | AMP + diphosphate + L-leucyl-tRNAGAGLeu | - |
? | |
ATP + L-leucine + tRNAGAGLeu | Pyrococcus horikoshii tRNAGAGLeu (PhtRNAGAGLeu) | Pyrococcus horikoshii | AMP + diphosphate + L-leucyl-tRNAGAGLeu | - |
? | |
ATP + L-leucine + tRNAGAGLeu | Pyrococcus horikoshii tRNAGAGLeu (PhtRNAGAGLeu) | Pyrococcus horikoshii ATCC 700860 / DSM 12428 / JCM 9974 / NBRC 100139 / OT-3 | AMP + diphosphate + L-leucyl-tRNAGAGLeu | - |
? | |
ATP + L-leucine + tRNALeu | - |
Homo sapiens | AMP + diphosphate + L-leucyl-tRNALeu | - |
? | |
ATP + L-leucine + tRNALeu | - |
Escherichia coli | AMP + diphosphate + L-leucyl-tRNALeu | - |
? | |
ATP + L-leucine + tRNALeu | - |
Mesomycoplasma mobile | AMP + diphosphate + L-leucyl-tRNALeu | - |
? | |
ATP + L-leucine + tRNALeu | - |
Aquifex aeolicus | AMP + diphosphate + L-leucyl-tRNALeu | - |
? | |
ATP + L-leucine + tRNALeu | - |
Pyrococcus horikoshii | AMP + diphosphate + L-leucyl-tRNALeu | - |
? | |
ATP + L-leucine + tRNALeu | - |
Mesomycoplasma mobile ATCC 43663 / 163K / NCTC 11711 | AMP + diphosphate + L-leucyl-tRNALeu | - |
? | |
ATP + L-leucine + tRNALeu | - |
Pyrococcus horikoshii ATCC 700860 / DSM 12428 / JCM 9974 / NBRC 100139 / OT-3 | AMP + diphosphate + L-leucyl-tRNALeu | - |
? | |
ATP + L-leucine + tRNAUAALeu | Mycoplasma mobile tRNAUAALeu (MmtRNAUAALeu) and mutat derivatives | Mesomycoplasma mobile | AMP + diphosphate + L-leucyl-tRNACAALeu | - |
? | |
ATP + L-leucine + tRNAUAALeu | Mycoplasma mobile tRNAUAALeu (MmtRNAUAALeu) and mutat derivatives | Mesomycoplasma mobile ATCC 43663 / 163K / NCTC 11711 | AMP + diphosphate + L-leucyl-tRNACAALeu | - |
? | |
ATP + L-leucine + tRNAUAALeu | Mycoplasma mobile MmtRNAUAALeu (Mmt-RNAUAALeu) | Escherichia coli | AMP + diphosphate + L-leucyl-tRNAUAALeu | - |
? |
Subunits | Comment | Organism |
---|---|---|
heterodimer | - |
Aquifex aeolicus |
Synonyms | Comment | Organism |
---|---|---|
AaLeuRS | - |
Aquifex aeolicus |
EcLeuRS | - |
Escherichia coli |
HcleuRS | - |
Homo sapiens |
Leucyl-tRNA synthetase | - |
Homo sapiens |
Leucyl-tRNA synthetase | - |
Escherichia coli |
Leucyl-tRNA synthetase | - |
Mesomycoplasma mobile |
Leucyl-tRNA synthetase | - |
Aquifex aeolicus |
Leucyl-tRNA synthetase | - |
Pyrococcus horikoshii |
LeuRS | - |
Homo sapiens |
LeuRS | - |
Escherichia coli |
LeuRS | - |
Mesomycoplasma mobile |
LeuRS | - |
Aquifex aeolicus |
LeuRS | - |
Pyrococcus horikoshii |
leuS | - |
Mesomycoplasma mobile |
leuS | - |
Pyrococcus horikoshii |
MmLeuRS | - |
Mesomycoplasma mobile |
PhLeuRS | - |
Pyrococcus horikoshii |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
30 | - |
assay at | Mesomycoplasma mobile |
37 | - |
assay at | Homo sapiens |
37 | - |
assay at | Escherichia coli |
37 | - |
assay at | Pyrococcus horikoshii |
65 | - |
assay at | Aquifex aeolicus |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.0055 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant mutant R703A | Pyrococcus horikoshii | |
0.017 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant mutant K696A | Pyrococcus horikoshii | |
0.02 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant wild-type enzyme | Pyrococcus horikoshii | |
0.041 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant mutant K692A | Pyrococcus horikoshii | |
0.05 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant mutant K699A | Pyrococcus horikoshii | |
0.067 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant mutant K698A | Pyrococcus horikoshii | |
0.18 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R668E/R672E | Escherichia coli | |
0.19 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R94E/R98E | Aquifex aeolicus | |
0.31 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R668A/R672A | Escherichia coli | |
0.53 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R672E | Escherichia coli | |
0.56 | - |
tRNACAGLeu | pH 7.8, 37°C, recombinant mutant R668A | Homo sapiens | |
0.59 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R668E | Escherichia coli | |
0.67 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R94A/R98A | Aquifex aeolicus | |
0.85 | - |
tRNAUAALeu | pH 7.8, 30°C, recombinant mutant K456E | Mesomycoplasma mobile | |
0.89 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R94E | Aquifex aeolicus | |
1 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R98E | Aquifex aeolicus | |
1.3 | - |
tRNAUAALeu | pH 7.8, 30°C, recombinant mutant K456A | Mesomycoplasma mobile | |
1.3 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R94A | Aquifex aeolicus | |
1.4 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R668A | Escherichia coli | |
1.5 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R98A | Aquifex aeolicus | |
1.5 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant wild-type enzyme | Aquifex aeolicus | |
2.6 | - |
tRNACAGLeu | pH 7.8, 37°C, recombinant wild-type enzyme | Homo sapiens | |
2.8 | - |
tRNAUAALeu | pH 7.8, 30°C, recombinant mutant K452E | Mesomycoplasma mobile | |
3.2 | - |
tRNAUAALeu | pH 7.8, 30°C, recombinant mutant K452A | Mesomycoplasma mobile | |
3.3 | - |
tRNAUAALeu | pH 7.8, 30°C, recombinant wild-type enzyme | Mesomycoplasma mobile | |
4.2 | - |
tRNAUAALeu | pH 7.5, 37°C, recombinant wild-type enzyme | Escherichia coli | |
4.8 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant K671A | Escherichia coli | |
4.8 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R672A | Escherichia coli | |
4.9 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant wild-type enzyme | Escherichia coli |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.5 | - |
assay at | Escherichia coli |
7.8 | - |
assay at | Homo sapiens |
7.8 | - |
assay at | Mesomycoplasma mobile |
7.8 | - |
assay at | Aquifex aeolicus |
7.8 | - |
assay at | Pyrococcus horikoshii |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
ATP | - |
Homo sapiens | |
ATP | - |
Escherichia coli | |
ATP | - |
Mesomycoplasma mobile | |
ATP | - |
Aquifex aeolicus | |
ATP | - |
Pyrococcus horikoshii |
General Information | Comment | Organism |
---|---|---|
evolution | based on sequence homology and the structures of the catalytic active sites, aaRSs are divided into two classes of 10 members each. Class I synthetases are further divided into three subclasses, a, b, and c, according to sequence homology. Leucyl-tRNA synthetase (LeuRS) belongs to class I aaRSs that include a typical Rossmann dinucleotide-binding fold active site architecture with the signature sequence modules HIGH and KMSKS. According to evolutionary models, the primitive catalytic core is extended by the insertion and/or fusion of additional domains (also called modules) in LeuRSs, most of which have inserted a large connective polypeptide 1 (CP1) domain that is responsible for amino acid editing. To ensure translation accuracy, LeuRSs have evolved a mechanism to remove aminoacyl AMP (aa-AMP, pre-transfer editing) and aa-tRNA (post-transfer editing). Sequence comparisons of the stem contact-fold domain (SC-fold) involved in editing, basic residues on helix alpha3 of the SC-fold are critical for catalytic efficiency, overview | Homo sapiens |
evolution | based on sequence homology and the structures of the catalytic active sites, aaRSs are divided into two classes of 10 members each. Class I synthetases are further divided into three subclasses, a, b, and c, according to sequence homology. Leucyl-tRNA synthetase (LeuRS) belongs to class I aaRSs that include a typical Rossmann dinucleotide-binding fold active site architecture with the signature sequence modules HIGH and KMSKS. According to evolutionary models, the primitive catalytic core is extended by the insertion and/or fusion of additional domains (also called modules) in LeuRSs, most of which have inserted a large connective polypeptide 1 (CP1) domain that is responsible for amino acid editing. To ensure translation accuracy, LeuRSs have evolved a mechanism to remove aminoacyl AMP (aa-AMP, pre-transfer editing) and aa-tRNA (post-transfer editing). Sequence comparisons of the stem contact-fold domain (SC-fold) involved in editing, basic residues on helix alpha3 of the SC-fold are critical for catalytic efficiency, overview | Aquifex aeolicus |
evolution | based on sequence homology and the structures of the catalytic active sites, aaRSs are divided into two classes of 10 members each. Class I synthetases are further divided into three subclasses, a, b, and c, according to sequence homology. Leucyl-tRNA synthetase (LeuRS) belongs to class I aaRSs that include a typical Rossmann dinucleotide-bindingfold active site architecture with the signature sequence modules HIGH and KMSKS. According to evolutionary models, the primitive catalytic core is extended by the insertion and/or fusion of additional domains (also called modules) in LeuRSs, most of which have inserted a large connective polypeptide 1 (CP1) domain that is responsible for amino acid editing. To ensure translation accuracy, LeuRSs have evolved a mechanism to remove aminoacyl AMP (aa-AMP, pre-transfer editing) and aa-tRNA (post-transfer editing). Although post-transfer editing is carried out by the CP1 domain in most LeuRSs, this domain has been naturally deleted in LeuRS from Mycoplasma mobile (MmLeuRS). Sequence comparisons of the stem contact-fold domain (SC-fold) involved in editing, basic residues on helix alpha3 of the SC-fold are critical for catalytic efficiency, overview | Mesomycoplasma mobile |
evolution | based on sequence homology and the structures of the catalytic active sites, aaRSs are divided into two classes of 10 members each. Class I synthetases are further divided into three subclasses, a, b, and c, according to sequence homology. Leucyl-tRNA synthetase (LeuRS) belongs to class I aaRSs that include a typical Rossmann dinucleotide-bindingfold active site architecture with the signature sequence modules HIGH and KMSKS. According to evolutionary models, the primitive catalytic core is extended by the insertion and/or fusion of additional domains (also called modules) in LeuRSs, most of which have inserted a large connective polypeptide 1 (CP1) domain that is responsible for amino acid editing. To ensure translation accuracy, LeuRSs have evolved a mechanism to remove aminoacyl AMP (aa-AMP, pre-transfer editing) and aa-tRNA (post-transfer editing). Sequence comparison of the EcLeuRS stem contact-fold domain (SC-fold) with editing-deficient enzymes suggests that key residues of this module have evolved an adaptive strategy to follow the editing functions of LeuRS, basic residues on helix alpha3 of the SC-fold are critical for catalytic efficiency, overview | Escherichia coli |
evolution | based on sequence homology and the structures of the catalytic active sites, aaRSs are divided into two classes of 10 members each. Class I synthetases are further divided into three subclasses, a, b, and c, according to sequence homology. Leucyl-tRNA synthetase (LeuRS) belongs to class I aaRSs that include a typical Rossmann dinucleotide-bindingfold active site architecture with the signature sequence modules HIGH and KMSKS. According to evolutionary models, the primitive catalytic core is extended by the insertion and/or fusion of additional domains (also called modules) in LeuRSs, most of which have inserted a large connective polypeptide 1 (CP1) domain that is responsible for amino acid editing. To ensure translation accuracy, LeuRSs have evolved a mechanism to remove aminoacyl AMP (aa-AMP, pre-transfer editing) and aa-tRNA (post-transfer editing). Sequence comparisons of the stem contact-fold domain (SC-fold) involved in editing, basic residues on helix alpha3 of the SC-fold are critical for catalytic efficiency, overview | Pyrococcus horikoshii |
malfunction | mutation of highly conserved basic residues on the third alpha-helix of the KMSKS catalytic loop domain impairs the affinity of LeuRS for the anticodon stem of tRNALeu, which decreases both aminoacylation and editing activities | Escherichia coli |
additional information | the KMSKS catalytic loop exhibits alpha-alpha-beta-alpha topology in class Ia and Ib aminoacyl-tRNA synthetases, two glycine residues on the third alpha-helix contribute to flexibility, leucine activation, and editing of LeuRS from Escherichia coli (EcLeuRS), acidic residues on the beta-strand enhance the editing activity of EcLeuRS and sense the size of the tRNALeu D-loop. Incorporation of acidic residues on the beta-strand stimulates the tRNA-dependent editing activity of the chimeric minimalist enzyme Mycoplasma mobile LeuRS fused to the connective polypeptide 1 editing domain and leucine-specific domain from EcLeuRS. Sequence comparison of the EcLeuRS stem contact-fold domain with editing-deficient enzymes suggests that key residues of this module have evolved an adaptive strategy to follow the editing functions of LeuRS. Amino acid residues Arg668 or Arg672 are not involved in the amino acid activation step but rather the second tRNA transfer step | Escherichia coli |
additional information | the KMSKS catalytic loop exhibits alpha-alpha-beta-alpha topology in class Ia and Ib aminoacyl-tRNA synthetases. Incorporation of acidic residues on the beta-strand stimulates the tRNA-dependent editing activity of the chimeric minimalist enzyme Mycoplasma mobile LeuRS fused to the connective polypeptide 1 editing domain and leucine-specific domain from EcLeuRS, acidic residues on the beta-strand enhance the editing activity of EcLeuRS and sense the size of the tRNALeu D-loop | Mesomycoplasma mobile |
physiological function | aminoacyl-tRNA synthetases (aaRSs) are a large and diverse family of enzymes that catalyze the attachment of amino acids to their cognate tRNAs in a two-step aminoacylation reaction as follows: 1. amino acid activation by ATP hydrolysis to form an aminoacyl-adenylate intermediate, and 2. transfer of the aminoacyl moiety from the intermediate to the cognate tRNA isoacceptor to form aminoacyl-tRNA (aa-tRNA) | Homo sapiens |
physiological function | aminoacyl-tRNA synthetases (aaRSs) are a large and diverse family of enzymes that catalyze the attachment of amino acids to their cognate tRNAs in a two-step aminoacylation reaction as follows: 1. amino acid activation by ATP hydrolysis to form an aminoacyl-adenylate intermediate, and 2. transfer of the aminoacyl moiety from the intermediate to the cognate tRNA isoacceptor to form aminoacyl-tRNA (aa-tRNA) | Escherichia coli |
physiological function | aminoacyl-tRNA synthetases (aaRSs) are a large and diverse family of enzymes that catalyze the attachment of amino acids to their cognate tRNAs in a two-step aminoacylation reaction as follows: 1. amino acid activation by ATP hydrolysis to form an aminoacyl-adenylate intermediate, and 2. transfer of the aminoacyl moiety from the intermediate to the cognate tRNA isoacceptor to form aminoacyl-tRNA (aa-tRNA) | Mesomycoplasma mobile |
physiological function | aminoacyl-tRNA synthetases (aaRSs) are a large and diverse family of enzymes that catalyze the attachment of amino acids to their cognate tRNAs in a two-step aminoacylation reaction as follows: 1. amino acid activation by ATP hydrolysis to form an aminoacyl-adenylate intermediate, and 2. transfer of the aminoacyl moiety from the intermediate to the cognate tRNA isoacceptor to form aminoacyl-tRNA (aa-tRNA) | Aquifex aeolicus |
physiological function | aminoacyl-tRNA synthetases (aaRSs) are a large and diverse family of enzymes that catalyze the attachment of amino acids to their cognate tRNAs in a two-step aminoacylation reaction as follows: 1. amino acid activation by ATP hydrolysis to form an aminoacyl-adenylate intermediate, and 2. transfer of the aminoacyl moiety from the intermediate to the cognate tRNA isoacceptor to form aminoacyl-tRNA (aa-tRNA) | Pyrococcus horikoshii |
kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
30 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R668E/R672E | Escherichia coli | |
30 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant mutant K696A | Pyrococcus horikoshii | |
50 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant mutant R703A | Pyrococcus horikoshii | |
80 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant mutant K699A | Pyrococcus horikoshii | |
90 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant mutant K692A | Pyrococcus horikoshii | |
110 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant wild-type enzyme | Pyrococcus horikoshii | |
110 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R668E | Escherichia coli | |
130 | - |
tRNAGAGLeu | pH 7.8, 37°C, recombinant mutant K698A | Pyrococcus horikoshii | |
140 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R668A/R672A | Escherichia coli | |
190 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R672E | Escherichia coli | |
220 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R94E/R98E | Aquifex aeolicus | |
330 | - |
tRNACAGLeu | pH 7.8, 37°C, recombinant mutant R668A | Homo sapiens | |
340 | - |
tRNAUAALeu | pH 7.8, 30°C, recombinant mutant K456E | Mesomycoplasma mobile | |
500 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R668A | Escherichia coli | |
600 | - |
tRNAUAALeu | pH 7.8, 30°C, recombinant mutant K456A | Mesomycoplasma mobile | |
830 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R94A/R98A | Aquifex aeolicus | |
1100 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R94E | Aquifex aeolicus | |
1500 | - |
tRNAUAALeu | pH 7.8, 30°C, recombinant mutant K452E | Mesomycoplasma mobile | |
1700 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R94A | Aquifex aeolicus | |
1900 | - |
tRNAUAALeu | pH 7.8, 30°C, recombinant mutant K452A | Mesomycoplasma mobile | |
2000 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant K671A | Escherichia coli | |
2000 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant mutant R672A | Escherichia coli | |
2200 | - |
tRNAUAALeu | pH 7.8, 30°C, recombinant wild-type enzyme | Mesomycoplasma mobile | |
2230 | - |
tRNAGAGLeu | pH 7.5, 37°C, recombinant wild-type enzyme | Escherichia coli | |
2600 | - |
tRNAUAALeu | pH 7.5, 37°C, recombinant wild-type enzyme | Escherichia coli | |
2600 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R98E | Aquifex aeolicus | |
3500 | - |
tRNACAGLeu | pH 7.8, 37°C, recombinant wild-type enzyme | Homo sapiens | |
4800 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant mutant R98A | Aquifex aeolicus | |
5000 | - |
tRNAGAGLeu | pH 7.8, 65°C, recombinant wild-type enzyme | Aquifex aeolicus |