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Escherichia coli K-12 substr. MG1655 Reaction:

Superclasses: Reactions Classified By Conversion TypeSimple ReactionsChemical Reactions
Reactions Classified By SubstrateSmall-Molecule Reactions

EC Number:,,,,,,

Enzymes and Genes:
acid phosphataseInferred from experiment: appA
P-loop guanosine triphosphataseInferred from experiment: yjiA
zinc-binding GTPaseInferred from experiment: yeiR
accessory protein for nickel incorporation into hydrogenase isoenzymesInferred from experiment: hypB
selenocysteyl-tRNA-specific translation elongation factorInferred from experiment: selB
50S ribosomal subunit stability factorInferred from experiment: der
GTPase associated with the 50S subunit of the ribosomeInferred from experiment: hflX
ribosome small subunit-dependent GTPase AInferred from experiment: rsgA
GTPase that interacts with methylmalonyl-CoA mutaseInferred from experiment: argK

Supersedes EC numbers:,,,,,

The direction shown, i.e. which substrates are on the left and right sides, is in accordance with the direction in which it was curated.

Most BioCyc compounds have been protonated to a reference pH value of 7.3. Please see the PGDB Concepts Guide for more information.

Mass balance status: Balanced.

Enzyme Commission Primary Name for nucleoside-triphosphate phosphatase

Enzyme Commission Synonyms for nucleoside-triphosphatase, nucleoside triphosphate phosphohydrolase, nucleoside-5-triphosphate phosphohydrolase, nucleoside 5-triphosphatase, unspecific diphosphate phosphohydrolase

Enzyme Commission Primary Name for heterotrimeric G-protein GTPase

Enzyme Commission Primary Name for small monomeric GTPase

Enzyme Commission Primary Name for protein-synthesizing GTPase

Enzyme Commission Synonyms for elongation factor (EF), initiation factor (IF), peptide-release or termination factor

Enzyme Commission Primary Name for signal-recognition-particle GTPase

Enzyme Commission Primary Name for dynamin GTPase

Enzyme Commission Primary Name for tubulin GTPase

Enzyme Commission Summary for
Also hydrolyses other nucleoside triphosphates, diphosphates, thiamine diphosphate and FAD.

Enzyme Commission Summary for
This group comprises GTP-hydrolyzing systems, where GTP and GDP alternate in binding. This group includes stimulatory and inhibitory G-proteins such as Gs, Gi, Go and Golf, targetting adenylate cyclase and/or K+ and Ca2+ channels; Gq stimulating phospholipase C; transducin activating cGMP phosphodiesterase; gustducin activating cAMP phosphodiesterase. Golf is instrumental in odour perception, transducin in vision and gustducin in taste recognition. At least 16 different α subunits (39-52 kDa), 5 β subunits (36 kDa) and 12 γ subunits (6-9 kDa) are known.

Enzyme Commission Summary for
A family of about 50 enzymes with a molecular mass of 21 kDa that are distantly related to the α-subunit of EC, heterotrimeric G-protein GTPase. They are involved in cell-growth regulation (Ras subfamily), membrane vesicle traffic and uncoating (Rab and ARF subfamilies), nuclear protein import (Ran subfamily) and organization of the cytoskeleton (Rho and Rac subfamilies).

Enzyme Commission Summary for
This enzyme comprises a family of proteins involved in prokaryotic as well as eukaryotic protein synthesis. In the initiation factor complex, it is IF-2b (98 kDa) that binds GTP and subsequently hydrolyses it in prokaryotes. In eukaryotes, it is eIF-2 (150 kDa) that binds GTP. In the elongation phase, the GTP-hydrolysing proteins are the EF-Tu polypeptide of the prokaryotic transfer factor (43 kDa), the eukaryotic elongation factor EF-1α (53 kDa), the prokaryotic EF-G (77 kDa), the eukaryotic EF-2 (70-110 kDa) and the signal recognition particle that play a role in endoplasmic reticulum protein synthesis (325 kDa). EF-Tu and EF-1α catalyse binding of aminoacyl-tRNA to the ribosomal A-site, while EF-G and EF-2 catalyse the translocation of peptidyl-tRNA from the A-site to the P-site. GTPase activity is also involved in polypeptide release from the ribosome with the aid of the pRFs and eRFs.

Enzyme Commission Summary for
Activity is associated with the signal-recognition particle (a protein- and RNA-containing structure involved in endoplasmic-reticulum-associated protein synthesis).

Enzyme Commission Summary for
An enzyme with a molecular mass of about 100 kDa that is involved in endocytosis and is instrumental in pinching off membrane vesicles [Warnock96, McClure, Oh98].

Enzyme Commission Summary for
An intrinsic activity of α-tubulin involved in tubulin folding, division plane formation in prokaryotic cells and others [Yu97a, Tian99, Roychowdhury99].

Citations: [Matsushita68, Lewis65, Brightwell68, Tong93, Hsieh96, Klinger03, Placzek07, Neer95, Sprang97, Bondarenko97, Ming98, Bourne91, Hall94, Geyer97, Vitale98, Krab98, Kurzchalia84, Kisselev, Rodnina97, Freistroffer97, Connolly91 , Connolly89, Smets76, Miller93, Freymann97]

Gene-Reaction Schematic

Gene-Reaction Schematic



Bondarenko97: Bondarenko VA, Desai M, Dua S, Yamazaki M, Amin RH, Yousif KK, Kinumi T, Ohashi M, Komori N, Matsumoto H, Jackson KW, Hayashi F, Usukura J, Lipkin VM, Yamazaki A (1997). "Residues within the polycationic region of cGMP phosphodiesterase gamma subunit crucial for the interaction with transducin alpha subunit. Identification by endogenous ADP-ribosylation and site-directed mutagenesis." J Biol Chem 272(25);15856-64. PMID: 9188484

Bourne91: Bourne HR, Sanders DA, McCormick F (1991). "The GTPase superfamily: conserved structure and molecular mechanism." Nature 349(6305);117-27. PMID: 1898771

Brightwell68: Brightwell R, Tappel AL (1968). "Lysosomal acid pyrophosphatase and acid phosphatase." Arch Biochem Biophys 124(1);333-43. PMID: 5661608

Connolly89: Connolly T, Gilmore R (1989). "The signal recognition particle receptor mediates the GTP-dependent displacement of SRP from the signal sequence of the nascent polypeptide." Cell 57(4);599-610. PMID: 2541918

Connolly91: Connolly T, Rapiejko PJ, Gilmore R (1991). "Requirement of GTP hydrolysis for dissociation of the signal recognition particle from its receptor." Science 252(5009);1171-3. PMID: 1851576

Freistroffer97: Freistroffer DV, Pavlov MY, MacDougall J, Buckingham RH, Ehrenberg M (1997). "Release factor RF3 in E.coli accelerates the dissociation of release factors RF1 and RF2 from the ribosome in a GTP-dependent manner." EMBO J 16(13);4126-33. PMID: 9233821

Freymann97: Freymann DM, Keenan RJ, Stroud RM, Walter P (1997). "Structure of the conserved GTPase domain of the signal recognition particle." Nature 385(6614);361-4. PMID: 9002524

Geyer97: Geyer M, Wittinghofer A (1997). "GEFs, GAPs, GDIs and effectors: taking a closer (3D) look at the regulation of Ras-related GTP-binding proteins." Curr Opin Struct Biol 7(6);786-92. PMID: 9434896

Hall94: Hall A (1994). "Small GTP-binding proteins and the regulation of the actin cytoskeleton." Annu Rev Cell Biol 10;31-54. PMID: 7888179

Hsieh96: Hsieh HL, Tong CG, Thomas C, Roux SJ (1996). "Light-modulated abundance of an mRNA encoding a calmodulin-regulated, chromatin-associated NTPase in pea." Plant Mol Biol 30(1);135-47. PMID: 8616230

Kisselev: Kisselev LL, Frolova LYu "Termination of translation in eukaryotes." Biochem Cell Biol 73(11-12);1079-86. PMID: 8722024

Klinger03: Klinger C, Rossbach M, Howe R, Kaufmann M (2003). "Thermophile-specific proteins: the gene product of aq_1292 from Aquifex aeolicus is an NTPase." BMC Biochem 4;12. PMID: 14503925

Krab98: Krab IM, Parmeggiani A (1998). "EF-Tu, a GTPase odyssey." Biochim Biophys Acta 1443(1-2);1-22. PMID: 9838020

Kurzchalia84: Kurzchalia TV, Bommer UA, Babkina GT, Karpova GG (1984). "GTP interacts with the gamma-subunit of eukaryotic initiation factor eIF-2." FEBS Lett 175(2);313-6. PMID: 6566615

Lewis65: Lewis M, Weissman S (1965). "Properties of a soluble nucleoside triphosphatase activity in mammalian liver." Arch Biochem Biophys 109;490-8. PMID: 14320490

Matsushita68: Matsushita S, Raacke ID (1968). "Purification of nucleoside triphosphatases from pea seedling ribosomes." Biochim Biophys Acta 166(3);707-10. PMID: 4301913

McClure: McClure SJ, Robinson PJ "Dynamin, endocytosis and intracellular signalling (review)." Mol Membr Biol 13(4);189-215. PMID: 9116759

Miller93: Miller JD, Wilhelm H, Gierasch L, Gilmore R, Walter P (1993). "GTP binding and hydrolysis by the signal recognition particle during initiation of protein translocation." Nature 366(6453);351-4. PMID: 8247130

Ming98: Ming D, Ruiz-Avila L, Margolskee RF (1998). "Characterization and solubilization of bitter-responsive receptors that couple to gustducin." Proc Natl Acad Sci U S A 95(15);8933-8. PMID: 9671782

Neer95: Neer EJ (1995). "Heterotrimeric G proteins: organizers of transmembrane signals." Cell 80(2);249-57. PMID: 7834744

Oh98: Oh P, McIntosh DP, Schnitzer JE (1998). "Dynamin at the neck of caveolae mediates their budding to form transport vesicles by GTP-driven fission from the plasma membrane of endothelium." J Cell Biol 141(1);101-14. PMID: 9531551

Placzek07: Placzek WJ, Almeida MS, Wuthrich K (2007). "NMR structure and functional characterization of a human cancer-related nucleoside triphosphatase." J Mol Biol 367(3);788-801. PMID: 17291528

Rodnina97: Rodnina MV, Savelsbergh A, Katunin VI, Wintermeyer W (1997). "Hydrolysis of GTP by elongation factor G drives tRNA movement on the ribosome." Nature 385(6611);37-41. PMID: 8985244

Roychowdhury99: Roychowdhury S, Panda D, Wilson L, Rasenick MM (1999). "G protein alpha subunits activate tubulin GTPase and modulate microtubule polymerization dynamics." J Biol Chem 274(19);13485-90. PMID: 10224115

Smets76: Smets LA, van Beek WP, van Rooij H (1976). "Surface glycoproteins and concanavalin-A-mediated agglutinability of clonal variants and tumour cells derived from SV40-virus-transformed mouse 3T3 cells." Int J Cancer 18(4);462-8. PMID: 185157

Sprang97: Sprang SR (1997). "G protein mechanisms: insights from structural analysis." Annu Rev Biochem 66;639-78. PMID: 9242920

Tian99: Tian G, Bhamidipati A, Cowan NJ, Lewis SA (1999). "Tubulin folding cofactors as GTPase-activating proteins. GTP hydrolysis and the assembly of the alpha/beta-tubulin heterodimer." J Biol Chem 274(34);24054-8. PMID: 10446175

Tong93: Tong CG, Dauwalder M, Clawson GA, Hatem CL, Roux SJ (1993). "The major nucleoside triphosphatase in pea (Pisum sativum L.) nuclei and in rat liver nuclei share common epitopes also present in nuclear lamins." Plant Physiol 101(3);1005-11. PMID: 7508630

Vitale98: Vitale N, Moss J, Vaughan M (1998). "Molecular characterization of the GTPase-activating domain of ADP-ribosylation factor domain protein 1 (ARD1)." J Biol Chem 273(5);2553-60. PMID: 9446556

Warnock96: Warnock DE, Schmid SL (1996). "Dynamin GTPase, a force-generating molecular switch." Bioessays 18(11);885-93. PMID: 8939066

Yu97a: Yu XC, Margolin W (1997). "Ca2+-mediated GTP-dependent dynamic assembly of bacterial cell division protein FtsZ into asters and polymer networks in vitro." EMBO J 16(17);5455-63. PMID: 9312004

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Please cite the following article in publications resulting from the use of EcoCyc: Nucleic Acids Research 41:D605-12 2013
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