Literature summary for 6.1.1.21 extracted from

Connolly, S.A.; Rosen, A.E.; Musier-Forsyth, K.; Francklyn, C.S.
G-1:C73 recognition by an arginine cluster in the active site of Escherichia coli histidyl-tRNA synthetase (2004), Biochemistry, 43, 962-969.

Search for more literature for 6.1.1.21

Cloned(Commentary)

Cloned (Comment)	Organism
DNA sequence determination and expression in strain JM105 of wild-type and mutant enzymes	Escherichia coli

Protein Variants

Protein Variants	Comment	Organism
Q118E	site-directed point mutagenesis of an active site residue, reduced kcat but unaltered Km with wild-type tRNAHis G-1	Escherichia coli
R116A	site-directed mutagenesis, reduced activity, increased specificity for the wild-type full length tRNAHis G-1	Escherichia coli
R123A	site-directed point mutagenesis of an active site residue, reduced activity, increased specificity for the wild-type full length tRNAHis G-1	Escherichia coli
R9H	site-directed point mutangenesis, increased activity with wild-type full length tRNAHis G-1, reduced activity with the synthetic tRNAHis G-1 and A-1 substrates, increased specificity for the wild-type full length tRNAHis G-1	Escherichia coli

KM Value [mM]

KM Value [mM]	KM Value Maximum [mM]	Substrate	Comment	Organism	Structure
additional information	-	additional information	kinetics and substrate specificity	Escherichia coli
0.00034	-	wild-type full length tRNAHis G-1	7.5, 37°C, wild-type enzyme	Escherichia coli
0.00096	-	synthetic tRNAHis A-1	7.5, 37°C, wild-type enzyme	Escherichia coli
0.0012	-	synthetic tRNAHis G-1	7.5, 37°C, wild-type enzyme	Escherichia coli
0.0025	-	synthetic tRNAHis G-1	7.5, 37°C, enzyme mutant R123A	Escherichia coli
0.0026	-	synthetic tRNAHis A-1	7.5, 37°C, enzyme mutant R123A	Escherichia coli
0.0048	-	wild-type full length tRNAHis G-1	7.5, 37°C, enzyme mutant R123A	Escherichia coli
0.0055	-	synthetic tRNAHis A-1	7.5, 37°C, enzyme mutant R9H	Escherichia coli
0.0058	-	wild-type full length tRNAHis G-1	7.5, 37°C, enzyme mutant R116A	Escherichia coli
0.0063	-	synthetic tRNAHis A-1	7.5, 37°C, enzyme mutant R116A	Escherichia coli
0.0081	-	synthetic tRNAHis G-1	7.5, 37°C, enzyme mutant R116A	Escherichia coli
0.015	-	wild-type full length tRNAHis G-1	7.5, 37°C, enzyme mutant R9H	Escherichia coli
0.0178	-	synthetic tRNAHis G-1	7.5, 37°C, enzyme mutant R9H	Escherichia coli

Metals/Ions

Metals/Ions	Comment	Organism	Structure
Mg2+	-	Escherichia coli

Natural Substrates/ Products (Substrates)

Natural Substrates	Organism	Comment (Nat. Sub.)	Natural Products	Comment (Nat. Pro.)	Rev.	Reac.
ATP + L-histidine + tRNAHis	Escherichia coli	-	AMP + diphosphate + L-histidyl-tRNAHis	-	?

Organism

Organism	UniProt	Comment	Textmining
Escherichia coli	-	-	-

Purification (Commentary)

Purification (Comment)	Organism
recombinant wild-type enzyme and mutants	Escherichia coli

Reaction

Reaction	Comment	Organism	Reaction ID
ATP + L-histidine + tRNAHis = AMP + diphosphate + L-histidyl-tRNAHis	interaction mechanism of RNA substrate and enzyme, active site structure	Escherichia coli	a

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.	Reac.
ATP + L-histidine + synthetic tRNAHis A-1	-	Escherichia coli	AMP + diphosphate + L-histidyl-tRNAHis	-	?
ATP + L-histidine + synthetic tRNAHis G-1	-	Escherichia coli	AMP + diphosphate + L-histidyl-tRNAHis	-	?
ATP + L-histidine + tRNAHis	-	Escherichia coli	AMP + diphosphate + L-histidyl-tRNAHis	-	?
ATP + L-histidine + wild-type full length tRNAHis G-1	activity is highly dependent upon the recognition of the unique G-1:C73 base pair and the 5'-monophosphate	Escherichia coli	AMP + diphosphate + L-histidyl-tRNAHis	-	?
additional information	substrate specificity for the N-1 base of wild-type enzyme and mutants, overview	Escherichia coli	?	-	?

Synonyms

Synonyms	Comment	Organism
HisRS	-	Escherichia coli
Histidine translase	-	Escherichia coli
histidine-tRNA ligase	-	Escherichia coli
histidine-tRNA ligase homolog	-	Escherichia coli
Histidyl-transfer ribonucleate synthetase	-	Escherichia coli
Histidyl-tRNA synthetase	-	Escherichia coli
Jo-1	-	Escherichia coli
Jo-1 antigen	-	Escherichia coli
Synthetase, histidyl-transfer ribonucleate	-	Escherichia coli

Temperature Optimum [°C]

Temperature Optimum [°C]	Temperature Optimum Maximum [°C]	Comment	Organism
25	-	assay at	Escherichia coli

Turnover Number [1/s]

Turnover Number Minimum [1/s]	Turnover Number Maximum [1/s]	Substrate	Comment	Organism	Structure
0.002	-	synthetic tRNAHis A-1	7.5, 37°C, enzyme mutant R123A	Escherichia coli
0.012	-	synthetic tRNAHis A-1	7.5, 37°C, enzyme mutant R116A	Escherichia coli
0.018	-	synthetic tRNAHis A-1	7.5, 37°C, wild-type enzyme	Escherichia coli
0.024	-	synthetic tRNAHis A-1	7.5, 37°C, enzyme mutant R9H	Escherichia coli
0.11	-	synthetic tRNAHis G-1	7.5, 37°C, enzyme mutant R123A	Escherichia coli
0.12	-	wild-type full length tRNAHis G-1	7.5, 37°C, enzyme mutant R123A	Escherichia coli
0.13	-	synthetic tRNAHis G-1	7.5, 37°C, enzyme mutant R116A	Escherichia coli
0.76	-	synthetic tRNAHis G-1	7.5, 37°C, enzyme mutant R9H	Escherichia coli
1.76	-	wild-type full length tRNAHis G-1	7.5, 37°C, enzyme mutant R116A	Escherichia coli
2.04	-	wild-type full length tRNAHis G-1	7.5, 37°C, wild-type enzyme	Escherichia coli
2.5	4	wild-type full length tRNAHis G-1	7.5, 37°C, enzyme mutant R9H	Escherichia coli
2.54	-	wild-type full length tRNAHis G-1	7.5, 37°C, enzyme mutant R9H	Escherichia coli
2.94	-	wild-type full length tRNAHis G-1	7.5, 37°C, enzyme mutant R116A	Escherichia coli
2.94	-	wild-type full length tRNAHis G-1	7.5, 37°C, wild-type enzyme	Escherichia coli
4.75	-	synthetic tRNAHis G-1	7.5, 37°C, wild-type enzyme	Escherichia coli
6.08	-	synthetic tRNAHis G-1	7.5, 37°C, enzyme mutant R9H	Escherichia coli

pH Optimum

pH Optimum Minimum	pH Optimum Maximum	Comment	Organism
7.5	-	assay at	Escherichia coli

Cofactor

Cofactor	Comment	Organism	Structure
ATP	-	Escherichia coli

Use of this online version of BRENDA is free under the CC BY 4.0 license. See terms of use for full details.

Release 2023.1 (January 2023)