Enzymes
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- Name help_outline H2O Identifier CHEBI:15377 (Beilstein: 3587155; CAS: 7732-18-5) help_outline Charge 0 Formula H2O InChIKeyhelp_outline XLYOFNOQVPJJNP-UHFFFAOYSA-N SMILEShelp_outline [H]O[H] 2D coordinates Mol file for the small molecule Search links Involved in 6,204 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline P1,P4-bis(5'-guanosyl) tetraphosphate Identifier CHEBI:57553 (Beilstein: 7331899) help_outline Charge -4 Formula C20H24N10O21P4 InChIKeyhelp_outline OLGWXCQXRSSQPO-MHARETSRSA-J SMILEShelp_outline Nc1nc2n(cnc2c(=O)[nH]1)[C@@H]1O[C@H](COP([O-])(=O)OP([O-])(=O)OP([O-])(=O)OP([O-])(=O)OC[C@H]2O[C@H]([C@H](O)[C@@H]2O)n2cnc3c2nc(N)[nH]c3=O)[C@@H](O)[C@H]1O 2D coordinates Mol file for the small molecule Search links Involved in 3 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline GDP Identifier CHEBI:58189 Charge -3 Formula C10H12N5O11P2 InChIKeyhelp_outline QGWNDRXFNXRZMB-UUOKFMHZSA-K SMILEShelp_outline Nc1nc2n(cnc2c(=O)[nH]1)[C@@H]1O[C@H](COP([O-])(=O)OP([O-])([O-])=O)[C@@H](O)[C@H]1O 2D coordinates Mol file for the small molecule Search links Involved in 184 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline H+ Identifier CHEBI:15378 Charge 1 Formula H InChIKeyhelp_outline GPRLSGONYQIRFK-UHFFFAOYSA-N SMILEShelp_outline [H+] 2D coordinates Mol file for the small molecule Search links Involved in 9,431 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
Cross-references
| RHEA:30203 | RHEA:30204 | RHEA:30205 | RHEA:30206 | |
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| Reaction direction help_outline | undefined | left-to-right | right-to-left | bidirectional |
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Publications
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Catabolism of diadenosine 5',5''-P1,P4-tetraphosphate in procaryotes. Purification and properties of diadenosine 5',5''-P1,P4-tetraphosphate (symmetrical) pyrophosphohydrolase from Escherichia coli K12.
Guranowski A., Jakubowski H., Holler E.
Enzymatic activity which hydrolyzes diadenosine 5',5"'-P1,P4-tetraphosphate (Ap4A) yielding ADP has been identified in extracts of eubacteria, Escherichia coli and Acidaminococcus fermentans, and of a highly thermophilic archaebacterium, Pyrodictum occultum. Specific Ap4A (symmetric) pyrophosphohy ... >> More
Enzymatic activity which hydrolyzes diadenosine 5',5"'-P1,P4-tetraphosphate (Ap4A) yielding ADP has been identified in extracts of eubacteria, Escherichia coli and Acidaminococcus fermentans, and of a highly thermophilic archaebacterium, Pyrodictum occultum. Specific Ap4A (symmetric) pyrophosphohydrolase from Escherichia coli K12 has been purified almost 400-fold. The preparation was free of phosphatase, ATPase, phosphodiesterase, AMP-nucleosidase, and adenylate kinase. The Ap4A pyrophosphohydrolase molecular weight estimated by gel filtration is 27,000 +/-1,000. Activity maximum is at pH 8.3. The Km value computed for Ap4A is 25 +/-3 microM. The sulfhydryl group(s) is essential for enzyme activity. Metal chelators, EDTA, and o-phenanthroline, inhibit Ap4A hydrolysis; I0.5 values are 3 and 50 microM, respectively. Co2+ is a strong stimulator with an almost 100-fold increase in rate of Ap4A hydrolysis and a plateau in the range of 100-500 microM Co2+, when compared with the nonstimulated hydrolysis. Other transition metal ions, Mn2+, Cd2+, and Ni2+, stimulate by factors of 8, 3.5, and 3.5, respectively, with optimal concentrations in the range 200-500, 2-5, and 4-8 microM, respectively. Zn2+, Cu2+, and Fe2+, up to 30 microM, are without effect and they inhibit at higher concentrations. Mg2+ or Ca2+, in the absence of other divalent metal ions, are weak stimulators (1.5-fold stimulation occurs at 1-2 mM concentration), but act synergistically with Co2+ at its suboptimal concentrations. Stimulation in the presence of 10 microM Co2+ and either 1 mM MgCl2 or CaCl2 increases up to 75-fold. The same degree of synergy is found at 10 microM Co2+ and either 2-5 mM spermidine or 0.5-1.5 mM spermine. Besides Ap4A, bacterial Ap4A pyrophosphohydrolase hydrolyzes effectively Ap5A and Gp4G, and, to some extent, p4A, Ap6A, and Ap3A yielding in each case corresponding nucleoside diphosphate as one of the products. << Less
J. Biol. Chem. 258:14784-14789(1983) [PubMed] [EuropePMC]
This publication is cited by 1 other entry.