Cloned (Comment) | Organism |
---|---|
expression of cytoplasmic and mitochondrial isozymes as GST-fusion proteins in the yeast strain RS453, functional complementation of an inactive gene disruption yeast strain by the mitochondrial isozyme located in the cytoplasm | Saccharomyces cerevisiae |
Protein Variants | Comment | Organism |
---|---|---|
A355C | site-directed mutagenesis, 115% activity compared to the wild-type enzyme, in vivo complementation of a deficient yeast strain | Saccharomyces cerevisiae |
C337A/C340A | site-directed mutagenesis, inactive | Saccharomyces cerevisiae |
C350A | site-directed mutagenesis, 1.5% activity compared to the wild-type enzyme, no in vivo complementation of a deficient yeast strain | Saccharomyces cerevisiae |
C350A/C353A | site-directed mutagenesis, inactive | Saccharomyces cerevisiae |
C353A | site-directed mutagenesis, catalytically inactive, no in vivo complementation of a deficient yeast strain | Saccharomyces cerevisiae |
C367A | site-directed mutagenesis, catalytically inactive, no in vivo complementation of a deficient yeast strain, mutant shows a second zinc-binding knuckle structure | Saccharomyces cerevisiae |
D348G | site-directed mutagenesis, 4.7% activity compared to the wild-type enzyme, in vivo complementation of a deficient yeast strain | Saccharomyces cerevisiae |
D370A | site-directed mutagenesis, 8.7% activity compared to the wild-type enzyme, in vivo complementation of a deficient yeast strain | Saccharomyces cerevisiae |
G347R | site-directed mutagenesis, catalytically inactive, no in vivo complementation of a deficient yeast strain | Saccharomyces cerevisiae |
I363N | site-directed mutagenesis, 84% activity compared to the wild-type enzyme, in vivo complementation of a deficient yeast strain | Saccharomyces cerevisiae |
additional information | construction of an inactive strain by gene disruption | Saccharomyces cerevisiae |
P338I | site-directed mutagenesis, 74% activity compared to the wild-type enzyme, in vivo complementation of a deficient yeast strain | Saccharomyces cerevisiae |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
1,10-phenanthroline | complete inhibition of the cytoplasmic isozyme at 1 mM | Saccharomyces cerevisiae |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.0004 | - |
tRNAMet | recombinant mitochondrial isozyme as GST-fusion protein, pH 7.8, 25°C | Saccharomyces cerevisiae | |
0.009 | - |
tRNAMet | recombinant cytoplasmic isozyme, pH 7.8, 25°C | Saccharomyces cerevisiae | |
0.015 | - |
tRNAMet | recombinant cytoplasmic isozyme as GST-fusion protein, pH 7.8, 25°C | Saccharomyces cerevisiae | |
1.2 | - |
CoA | methionylation reaction, cytoplasmic isozyme, pH 7.8, 25°C | Saccharomyces cerevisiae | |
1.8 | - |
L-homocysteine | editing reaction, mitochondrial isozyme, pH 7.8, 25°C | Saccharomyces cerevisiae | |
3.1 | - |
L-homocysteine | editing reaction, cytoplasmic isozyme, pH 7.8, 25°C | Saccharomyces cerevisiae | |
6.3 | - |
CoA | methionylation reaction, mitochondrial isozyme, pH 7.8, 25°C | Saccharomyces cerevisiae |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
cytoplasm | cytoplasmic isozyme has a zinc-finger motif and an insertion domain that divides the nucleotide-binding fold into 2 halves | Saccharomyces cerevisiae | 5737 | - |
mitochondrion | mitochondrial isozyme contains no zinc-finger motif and no insertion domain in the nucleotide-binding fold | Saccharomyces cerevisiae | 5739 | - |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Zn2+ | 2 binding sites, 0.14 mM tightly bound zinc is present in 1 mol of cytoplasmic isozyme, but not in the mitochondrial one, required for stability and activity of the cytoplasmic isozyme | Saccharomyces cerevisiae |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + L-homocysteine + tRNAMet | Saccharomyces cerevisiae | edition and aminoacylation by cytoplasmic and mitochondrial isozyme | ? | - |
? | |
ATP + L-methionine + tRNAMet | Saccharomyces cerevisiae | initiator and elongation tRNAMet, cytoplasmic and mitochondrial isozyme | AMP + diphosphate + L-methionyl-tRNAMet | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Saccharomyces cerevisiae | - |
2 cytoplasmic and mitochondrial isozymes | - |
Purification (Comment) | Organism |
---|---|
recombinant GST-fusion protein of the mitochondrial isozyme | Saccharomyces cerevisiae |
Reaction | Comment | Organism | Reaction ID |
---|---|---|---|
ATP + L-methionine + tRNAMet = AMP + diphosphate + L-methionyl-tRNAMet | amino acid residues D138, R139, and F135 are important for activity | Saccharomyces cerevisiae |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + L-homocysteine + tRNAMet | edition and aminoacylation by cytoplasmic and mitochondrial isozyme | Saccharomyces cerevisiae | ? | - |
? | |
ATP + L-methionine + tRNAMet | initiator and elongation tRNAMet, cytoplasmic and mitochondrial isozyme | Saccharomyces cerevisiae | AMP + diphosphate + L-methionyl-tRNAMet | - |
? | |
CoA + L-methionine | - |
Saccharomyces cerevisiae | Met-S-CoA | - |
? | |
additional information | the isozymes also perform the ATP-diphosphate exchange reaction | Saccharomyces cerevisiae | ? | - |
? |
Synonyms | Comment | Organism |
---|---|---|
Methionine translase | - |
Saccharomyces cerevisiae |
Methionine--tRNA ligase | - |
Saccharomyces cerevisiae |
Methionyl tRNA synthetase | - |
Saccharomyces cerevisiae |
Methionyl-transfer ribonucleate synthetase | - |
Saccharomyces cerevisiae |
Methionyl-transfer ribonucleic acid synthetase | - |
Saccharomyces cerevisiae |
Methionyl-transfer RNA synthetase | - |
Saccharomyces cerevisiae |
MetRS | - |
Saccharomyces cerevisiae |
Synthetase, methionyl-transfer ribonucleate | - |
Saccharomyces cerevisiae |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.2 | - |
tRNAMet | recombinant mitochondrial isozyme as GST-fusion protein, pH 7.8, 25°C | Saccharomyces cerevisiae | |
0.5 | - |
L-homocysteine | editing reaction, mitochondrial isozyme, pH 7.8, 25°C | Saccharomyces cerevisiae | |
0.69 | - |
L-homocysteine | editing reaction, cytoplasmic isozyme, pH 7.8, 25°C | Saccharomyces cerevisiae | |
0.7 | - |
CoA | methionylation reaction, cytoplasmic isozyme, pH 7.8, 25°C | Saccharomyces cerevisiae | |
1 | - |
tRNAMet | recombinant cytoplasmic isozyme as GST-fusion protein, pH 7.8, 25°C | Saccharomyces cerevisiae | |
1.3 | - |
tRNAMet | recombinant cytoplasmic isozyme, pH 7.8, 25°C | Saccharomyces cerevisiae | |
1.6 | - |
CoA | methionylation reaction, mitochondrial isozyme, pH 7.8, 25°C | Saccharomyces cerevisiae | |
6.08 | - |
L-homocysteine | editing reaction, cytoplasmic isozyme, pH 7.8, 25°C | Saccharomyces cerevisiae |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
ATP | - |
Saccharomyces cerevisiae |