Cofactors

There are no Cofactors for this Enzyme

Reaction Mechanism

inorganic diphosphatase By Reference

Soluble inorganic pyrophosphate is present in all organisms, and is essential for cell growth. It provides an entropic pull for biosynthetic reactions involving nucleotide triphosphates by irreversibly hydrolysing the pyrophosphate product to orthophosphate. The phosphoryltransferase activity is an ancient one, and there are functional similarities between the active site of this enzyme and alkaline phosphatase and other divalent cation containing enzymes such as exonucleases and polymerases.




• Summary
• Step 1
• Step 2
• Step 3
• Products

This reaction begins with the coordination of three divalent metal ions into the active site as well as a water molecule from the aqueous solution. The metal ions coordinate a diphosphate into the active site while Asp89 deprotonates a water molecule. The resulting hydroxide attacks the proximal phosphate. This, in combination with the metals dissociating from the active site results in the release of two phosphate molecules. His21 and His86 are responsible for divalent metal selectivity and are major features distinguishing the Mtb PPiase from other characterised PPiases but aren't shown in this mechanism because they don't directly contribute to the catalysis reaction.

Catalytic Residues

AA	Uniprot	Uniprot Resid	PDB	PDB Resid
Asp		57	4z71	66
Asp		89	4z71	98
Asp		52	4z71	61
Glu		8	4z71	17
Asp		84	4z71	93
Tyr		42	4z71	51

Step Components

overall product formed, proton transfer, overall reactant used, coordination to a metal ion, bimolecular nucleophilic substitution



Step 1.

A divalent metal ion M3 binds to the PPiase, which already contains the divalent metal ion M1 in its active site. The presence of the two metal ions enable the binding of PPi together with a third divalent metal ion: M2.



Step 2.

The binding events are followed by the deprotonation of a water molecule by Asp89 and subsequent attack on the adjacent phosphate group of PPi by the resulting hydroxide, leading to the formation of the products.



Step 3.

After catalysis, ion M3 leaves the active site, followed by both phosphates and M2. Also, Asp89 is deprotonated (here inferred to be by a water molecule from solvent), thereby restoring the initial state of enzyme.



Products.

The products of the reaction.

View Reaction Mechanisms in M-CSA

Reaction Parameters

There are no kinetic parameters information for this Enzyme

Associated Proteins

Citations

• lista-GEM: the genome-scale metabolic reconstruction ofLipomyces starkeyi
• Transcriptome Analysis of Campylobacter jejuni and Campylobacter coli during Cold Stress.
• Comparative proteome analysis revealed the differences in response to both Mycobacterium tuberculosis and Mycobacterium bovis infection of bovine alveolar macrophages.
• The Pathogenesis of Diabetes.
• A meta-QTL analysis highlights genomic hotspots associated with phosphorus use efficiency in rice (Oryza sativa L.).
• Functional Potential of Soil Microbial Communities and Their Subcommunities Varies with Tree Mycorrhizal Type and Tree Diversity.
• Investigation the global effect of rare earth gadolinium on the budding Saccharomyces cerevisiae by genome-scale screening.
• In Situ Molecular Ecological Analyses Illuminate Distinct Factors Regulating Formation and Demise of a Harmful Dinoflagellate Bloom.
• Does the LHPP gene share a common biological function in pancancer progression?
• Genome-wide association analysis revealed genetic variation and candidate genes associated with the yield traits of upland cotton under drought conditions.
• Research Progress in Improving Photosynthetic Efficiency.