Literature summary for 2.7.99.B1 extracted from

Wright, M.; Boonyalai, N.; Tanner, J.A.; Hindley, A.D.; Miller, A.D.
The duality of LysU, a catalyst for both Ap4A and Ap3A formation (2006), FEBS J., 273, 3534-3544.

Search for more literature for 2.7.99.B1

General Stability

General Stability	Organism
phosphorylated LysU is able to retain activity (70% activity after 7 days) for significantly longer after storage at 4°C than unphosphorylated LysU (30% activity after 7 days), suggesting that phosphorylated LysU is significantly more stable than nonphosphorylated LysU.	Escherichia coli

KM Value [mM]

KM Value [mM]	KM Value Maximum [mM]	Substrate	Comment	Organism	Structure
4	-	ATP	phosphorylated LysU, kinetic constants derived from lysyl-adenylate, enzyme-coupled assay	Escherichia coli
6	-	ATP	phosphorylated LysU, kinetic constants derived from 1H-NMR 5,5-P1,P4-tetraphosphate synthesis	Escherichia coli
7	-	ATP	unphosphorylated LysU, kinetic constants derived from 1H-NMR 5,5-P1,P4-tetraphosphate synthesis	Escherichia coli
9.6	-	ATP	unphosphorylated LysU, kinetic constants derived from lysyl-adenylate, enzyme-coupled assay	Escherichia coli

Metals/Ions

Metals/Ions	Comment	Organism	Structure
Mg2+	-	Escherichia coli
Zn2+	-	Escherichia coli

Organism

Organism	UniProt	Comment	Textmining
Escherichia coli	-	-	-

Posttranslational Modification

Posttranslational Modification	Comment	Organism
phosphoprotein	phosphorylated LysU is significantly more stable than nonphosphorylated LysU	Escherichia coli

Reaction

Reaction	Comment	Organism	Reaction ID
2 ATP = diadenosine 5',5''''-P1,P4-tetraphosphate + diphosphate	overall reaction. LysU possesses a dual catalytic activity, initially producing 5,5-P1,P4-tetraphosphate from ATP, before converting that tetraphosphate to a triphosphate (diadenosine 5,5-P1,P3-triphosphate (Ap3A) synthase activity). It is shown that 5,5-P1,P3-triphosphate formation requires (1) that the second step of 5,5-P1,P4-tetraphosphate formation is slightly reversible, leading to a reappearance of adenylate intermediate, and (2) that phosphate is present to trap the intermediate. 5,5-P1,P3-triphosphate forms readily from 5,5-P1,P4-tetraphosphate in the presence of phosphate-based adenylate traps via a reverse-trap mechanism (5,5-P1,P4-tetraphosphate + diphosphate= 5,5-P1,P3-triphosphate + phosphate)	Escherichia coli	a

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.	Reac.
ATP + ATP	-	Escherichia coli	P1,P4-bis(5'-adenosyl)tetraphosphate + diphosphate	-	?

Synonyms

Synonyms	Comment	Organism
diadenosine 5',5''''-P1,P4-tetraphosphate synthase	diphosphate-forming	Escherichia coli
LysU	-	Escherichia coli

Temperature Optimum [°C]

Temperature Optimum [°C]	Temperature Optimum Maximum [°C]	Comment	Organism
37	-	assy at	Escherichia coli

Turnover Number [1/s]

Turnover Number Minimum [1/s]	Turnover Number Maximum [1/s]	Substrate	Comment	Organism	Structure
2	-	ATP	phosphorylated LysU, kinetic constants derived from 1H-NMR 5,5-P1,P4-tetraphosphate synthesis	Escherichia coli
2.7	-	ATP	unphosphorylated LysU, kinetic constants derived from 1H-NMR 5,5-P1,P4-tetraphosphate synthesis	Escherichia coli
12.2	-	ATP	phosphorylated LysU, kinetic constants derived from lysyl-adenylate, enzyme-coupled assay	Escherichia coli
16	-	ATP	unphosphorylated LysU, kinetic constants derived from lysyl-adenylate, enzyme-coupled assay	Escherichia coli

pH Optimum

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

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Release 2023.1 (January 2023)