Structural highlights
Function
[IPYR1_ARATH] Catalyzes the irreversible hydrolysis of pyrophosphate (PPi) to phosphate. The MgPPi(2-) complex binds to the enzyme only after a free Mg(2+) ion has bound (Ref.9). No activity with glycerol-3-phosphate, glucose-6-phosphate, p-nitrophenylphosphate, ADP, NADP(+), NAD(+),NADH, NADPH or phosphoribosyl pyrophosphate as substrates (Ref.9). Controls the equilibrium of gluconeogenic reactions in the heterotrophic growth phase of early seedling establishment. Determinates the rate of cytosolic glycolysis, providing carbon for seed storage lipid accumulation (PubMed:22566496).[1] [REFERENCE:9]
Publication Abstract from PubMed
Inorganic pyrophosphatase (PPase) is a ubiquitous cytosolic enzyme which catalyzes the hydrolysis of inorganic pyrophosphate (PPi) to orthophosphate (Pi). The crystal structure of inorganic pyrophosphatase from Helicobacter pylori (H-PPase) has been solved by MAD and refined to an R factor of 20.6% at 2.6 A resolution. The crystallographic asymmetric unit contains a homohexameric H-PPase arranged as a dimer of trimers. While most of the structural elements of PPases are highly conserved in H-PPase, some unique structural features are localized in the flexible loops near the active site, suggesting that the structural flexibility of these loops is required for the catalytic efficiency of PPase.
Structure of inorganic pyrophosphatase from Helicobacter pylori.,Wu CA, Lokanath NK, Kim DY, Park HJ, Hwang HY, Kim ST, Suh SW, Kim KK Acta Crystallogr D Biol Crystallogr. 2005 Nov;61(Pt 11):1459-64. Epub 2005, Oct 19. PMID:16239722[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Meyer K, Stecca KL, Ewell-Hicks K, Allen SM, Everard JD. Oil and protein accumulation in developing seeds is influenced by the expression of a cytosolic pyrophosphatase in Arabidopsis. Plant Physiol. 2012 Jul;159(3):1221-34. doi: 10.1104/pp.112.198309. Epub 2012 May, 7. PMID:22566496 doi:http://dx.doi.org/10.1104/pp.112.198309
- ↑ Wu CA, Lokanath NK, Kim DY, Park HJ, Hwang HY, Kim ST, Suh SW, Kim KK. Structure of inorganic pyrophosphatase from Helicobacter pylori. Acta Crystallogr D Biol Crystallogr. 2005 Nov;61(Pt 11):1459-64. Epub 2005, Oct 19. PMID:16239722 doi:10.1107/S0907444905025667
