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| | <StructureSection load='5a68' size='340' side='right'caption='[[5a68]], [[Resolution|resolution]] 1.67Å' scene=''> | | <StructureSection load='5a68' size='340' side='right'caption='[[5a68]], [[Resolution|resolution]] 1.67Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[5a68]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Arath Arath]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5A68 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5A68 FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[5a68]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Arabidopsis_thaliana Arabidopsis thaliana]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5A68 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5A68 FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=MN:MANGANESE+(II)+ION'>MN</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</scene></td></tr> | + | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MN:MANGANESE+(II)+ION'>MN</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</scene></td></tr> |
| - | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[5a5y|5a5y]], [[5a60|5a60]], [[5a61|5a61]], [[5a64|5a64]], [[5a65|5a65]], [[5a66|5a66]], [[5a67|5a67]]</td></tr>
| + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=5a68 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5a68 OCA], [https://pdbe.org/5a68 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5a68 RCSB], [https://www.ebi.ac.uk/pdbsum/5a68 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5a68 ProSAT]</span></td></tr> |
| - | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5a68 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5a68 OCA], [http://pdbe.org/5a68 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5a68 RCSB], [http://www.ebi.ac.uk/pdbsum/5a68 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5a68 ProSAT]</span></td></tr> | + | |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[http://www.uniprot.org/uniprot/TTM3_ARATH TTM3_ARATH]] Involved in the hydrolysis of the beta-gamma-phosphoanhydride linkage of triphosphate-containing substrates (inorganic or nucleoside-linked). Catalyzes the hydrolysis of inorganic triphosphate (PPPi), however it does not display significant activity towards long-chain polyphosphates. The existence of PPPi in living cells is still unclear, and PPPase activity might be the ancestral function of CYTH domain. It also has gamma-phosphatase activity on NTP substrates, but no adenylate cyclase or RNA triphosphatase activity.<ref>PMID:24004165</ref> | + | [https://www.uniprot.org/uniprot/TTM3_ARATH TTM3_ARATH] Involved in the hydrolysis of the beta-gamma-phosphoanhydride linkage of triphosphate-containing substrates (inorganic or nucleoside-linked). Catalyzes the hydrolysis of inorganic triphosphate (PPPi), however it does not display significant activity towards long-chain polyphosphates. The existence of PPPi in living cells is still unclear, and PPPase activity might be the ancestral function of CYTH domain. It also has gamma-phosphatase activity on NTP substrates, but no adenylate cyclase or RNA triphosphatase activity.<ref>PMID:24004165</ref> |
| | <div style="background-color:#fffaf0;"> | | <div style="background-color:#fffaf0;"> |
| | == Publication Abstract from PubMed == | | == Publication Abstract from PubMed == |
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| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: Arath]] | + | [[Category: Arabidopsis thaliana]] |
| | [[Category: Large Structures]] | | [[Category: Large Structures]] |
| - | [[Category: Hothorn, M]] | + | [[Category: Hothorn M]] |
| - | [[Category: Martinez, J]] | + | [[Category: Martinez J]] |
| - | [[Category: Truffault, V]] | + | [[Category: Truffault V]] |
| - | [[Category: Hydrolase]]
| + | |
| - | [[Category: Inorganic polyphosphate]]
| + | |
| - | [[Category: Triphosphate tunnel metalloenzyme]]
| + | |
| - | [[Category: Tripolyphosphate]]
| + | |
| Structural highlights
Function
TTM3_ARATH Involved in the hydrolysis of the beta-gamma-phosphoanhydride linkage of triphosphate-containing substrates (inorganic or nucleoside-linked). Catalyzes the hydrolysis of inorganic triphosphate (PPPi), however it does not display significant activity towards long-chain polyphosphates. The existence of PPPi in living cells is still unclear, and PPPase activity might be the ancestral function of CYTH domain. It also has gamma-phosphatase activity on NTP substrates, but no adenylate cyclase or RNA triphosphatase activity.[1]
Publication Abstract from PubMed
Triphosphate tunnel metalloenzymes (TTMs) are present in all kingdoms of life and catalyze diverse enzymatic reactions such as mRNA capping, the cyclization of adenosine triphosphate, the hydrolysis of thiamine triphosphate and the synthesis and breakdown of inorganic polyphosphates. TTMs have an unusual tunnel domain fold that harbors substrate- and metal co-factor binding sites. It is presently poorly understood how TTMs specifically sense different triphosphate-containing substrates and how catalysis occurs in the tunnel center. Here we describe substrate-bound structures of inorganic polyphosphatases from Arabidopsis and E. coli, which reveal an unorthodox yet conserved mode of triphosphate and metal co-factor binding. We identify two metal binding sites in these enzymes, with one co-factor involved in substrate coordination and the other in catalysis. Structural comparisons with a substrate- and product-bound mammalian thiamine triphosphatase, and with previously reported structures of mRNA capping enzymes, adenylate cyclases and polyphosphate polymerases, suggest that directionality of substrate binding defines TTM catalytic activity. Our work provides insight into the evolution and functional diversification of an ancient enzyme family.
Structural Determinants for Substrate Binding and Catalysis in Triphosphate Tunnel Metalloenzymes.,Martinez J, Truffault V, Hothorn M J Biol Chem. 2015 Jul 28. pii: jbc.M115.674473. PMID:26221030[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Moeder W, Garcia-Petit C, Ung H, Fucile G, Samuel MA, Christendat D, Yoshioka K. Crystal structure and biochemical analyses reveal that the Arabidopsis triphosphate tunnel metalloenzyme AtTTM3 is a tripolyphosphatase involved in root development. Plant J. 2013 Nov;76(4):615-26. doi: 10.1111/tpj.12325. Epub 2013 Oct 17. PMID:24004165 doi:http://dx.doi.org/10.1111/tpj.12325
- ↑ Martinez J, Truffault V, Hothorn M. Structural Determinants for Substrate Binding and Catalysis in Triphosphate Tunnel Metalloenzymes. J Biol Chem. 2015 Jul 28. pii: jbc.M115.674473. PMID:26221030 doi:http://dx.doi.org/10.1074/jbc.M115.674473
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