Literature summary for 3.6.1.1 extracted from

Chao, T.; Huang, H.; Tsai, J.; Huang, C.; Sun, Y.
Kinetic and structural properties of inorganic pyrophosphatase from the pathogenic bacterium Helicobacter pylori (2006), Proteins, 65, 670-680.

Activating Compound

Activating Compound	Comment	Organism	Structure
diphosphate	diphosphate binds Mg2+ to form a true substrate that activates the enzyme	Helicobacter pylori

Cloned(Commentary)

Cloned (Comment)	Organism
expression of His-tagged enzyme in Escherichia coli	Helicobacter pylori

Crystallization (Commentary)

Crystallization (Comment)	Organism
purified recombinant enzyme, free and in complex with diphosphate, hanging drop vapor diffusion method, for the free enzyme: 20 mg/ml protein in 20 mM Tris-HCl, pH 7.5, and 200 mM NaCl, precipitation with 1.44 M sodium citrate, and 100 mM Na HEPES, pH 7.4, 6 days at 25°C, for the diphosphate-bound enzyme: the diphosphate-PPase complex from the same buffer condition as the free enzyme with a 1:7.5 molar excess of K4diphosphate in the absence of divalent metal ion, the complex crystals are grown in the same buffer as free PPase using 3.6 M sodium formate as a precipitant, 3 days at 25°C, X-ray diffraction structure determination and analysis at 1.9 A and 2.3 A resolution, respectively, molecular replacement	Helicobacter pylori

Crystallization (Comment)

Organism

purified recombinant enzyme, free and in complex with diphosphate, hanging drop vapor diffusion method, for the free enzyme: 20 mg/ml protein in 20 mM Tris-HCl, pH 7.5, and 200 mM NaCl, precipitation with 1.44 M sodium citrate, and 100 mM Na HEPES, pH 7.4, 6 days at 25°C, for the diphosphate-bound enzyme: the diphosphate-PPase complex from the same buffer condition as the free enzyme with a 1:7.5 molar excess of K4diphosphate in the absence of divalent metal ion, the complex crystals are grown in the same buffer as free PPase using 3.6 M sodium formate as a precipitant, 3 days at 25°C, X-ray diffraction structure determination and analysis at 1.9 A and 2.3 A resolution, respectively, molecular replacement

Helicobacter pylori

Inhibitors

Inhibitors	Comment	Organism
ATP	50% inhibition at 2 mM, 90% at 3 mM ATP	Helicobacter pylori
imidodiphosphoric acid	a nonhydrolyzable PPi analogue, inhibits by 50% at 2 mM	Helicobacter pylori
N-ethylmaleimide	inhibits 38% of PPase activity at 37.5 mM	Helicobacter pylori
NaF	inhibits 46% and 91.4% of the activity at 0.04 mM and 0.5 mM, respectively	Helicobacter pylori

KM Value [mM]

KM Value [mM]	KM Value Maximum [mM]	Substrate	Comment	Organism	Structure
additional information	-	additional information	kinetics	Helicobacter pylori
0.214	-	diphosphate	recombinant enzyme	Helicobacter pylori

Localization

Localization	Comment	Organism	GeneOntology No.	Textmining
cytosol	-	Helicobacter pylori	5829	-

Metals/Ions

Metals/Ions	Comment	Organism	Structure
Mg2+	required, binds to diphosphate, effects on enzyme activity and kinetics, pH-dependence, overview	Helicobacter pylori

Molecular Weight [Da]

Molecular Weight [Da]	Molecular Weight Maximum [Da]	Comment	Organism
20675	-	6 * 20675, recombinant His-tagged enzyme, mass spectrometry	Helicobacter pylori
121000	-	recombinant His-tagged enzyme, gel filtration	Helicobacter pylori

Natural Substrates/ Products (Substrates)

Natural Substrates	Organism	Comment (Nat. Sub.)	Natural Products	Comment (Nat. Pro.)	Rev.	Reac.
diphosphate + H2O	Helicobacter pylori	PPase plays an essential role in energy conservation and provides the energy for many biosynthetic pathways controlling the intracellular diphosphate levels	2 phosphate	-	?

Organism

Organism	UniProt	Comment	Textmining
Helicobacter pylori	P56153	-	-

Purification (Commentary)

Purification (Comment)	Organism
recombinant His-tagged enzyme from Escherichia coli to homogeneity by nickel affinity chromatography and gel filtration	Helicobacter pylori

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.	Reac.
diphosphate + H2O	PPase plays an essential role in energy conservation and provides the energy for many biosynthetic pathways controlling the intracellular diphosphate levels	Helicobacter pylori	2 phosphate	-	?
diphosphate + H2O	diphosphate binding does not cause a significant conformational change in the diphosphate-PPase complex, structure, overview	Helicobacter pylori	2 phosphate	-	?

Subunits

Subunits	Comment	Organism
hexamer	6 * 20675, recombinant His-tagged enzyme, mass spectrometry	Helicobacter pylori
More	structure analysis, PPase comprises three alpha-helices and nine beta-strands and folds as a barrel structure, it forms a hexamer in both the solution and crystal states, and each monomer has its own PPi-binding site	Helicobacter pylori

Synonyms

Synonyms	Comment	Organism
inorganic pyrophosphatase	-	Helicobacter pylori
PPase	-	Helicobacter pylori

Temperature Optimum [°C]

Temperature Optimum [°C]	Temperature Optimum Maximum [°C]	Comment	Organism
37	-	assay at	Helicobacter pylori

pH Optimum

pH Optimum Minimum	pH Optimum Maximum	Comment	Organism
7.5	-	assay at	Helicobacter pylori