View source for 5xd1


==Crystal structure of Mycobacterium smegmatis MutT1 in complex with Ap5A, ATP and magnesium==
<StructureSection load='5xd1' size='340' side='right'caption='[[5xd1]], [[Resolution|resolution]] 1.60&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5xd1]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Mycolicibacterium_smegmatis_MC2_155 Mycolicibacterium smegmatis MC2 155]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5XD1 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5XD1 FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.6&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=5FA:ADENOSINE-5-PENTAPHOSPHATE'>5FA</scene>, <scene name='pdbligand=ATP:ADENOSINE-5-TRIPHOSPHATE'>ATP</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></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=5xd1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5xd1 OCA], [https://pdbe.org/5xd1 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5xd1 RCSB], [https://www.ebi.ac.uk/pdbsum/5xd1 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5xd1 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/MUTT1_MYCS2 MUTT1_MYCS2] Catalyzes the conversion of 8-oxo-dGTP to 8-oxo-dGDP, and 8-oxo-GTP to 8-oxo-GDP (PubMed:16585780, PubMed:28375146). At high enzyme concentrations, can also catalyze the conversion of 8-oxo-dGDP to 8-oxo-dGMP, and 8-oxo-GDP to 8-oxo-GMP (PubMed:28375146). In addition, catalyzes the hydrolysis of the diadenosine polyphosphates diadenosine hexaphosphate (Ap6A), diadenosine pentaphosphate (Ap5A) and diadenosine tetraphosphate (Ap4A) (PubMed:28705712).<ref>PMID:16585780</ref> <ref>PMID:28375146</ref> <ref>PMID:28705712</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Diadenosine polyphosphates (ApnA, n=2-6), particularly Ap4A, are involved in several important physiological processes. The substantial sequence identity of the Nudix hydrolase domain (domain 1) of Mycobacterium smegmatis MutT1 (MsMutT1) with a known Ap4A hydrolase suggested that MsMutT1 could also hydrolyse diadenosine polyphosphates. Biochemical experiments yielded results in conformity with this suggestion, with Ap4A as the best among the substrates. ATP is a product in all experiments; small amounts of ADP were also observed in the experiments involving Ap4A and Ap6A. Hydrolysis was inhibited by fluoride ions in all cases. The mechanism of action and its inhibition in relation to ApnA were explored through the X-ray analysis of the crystals of the MsMutT1 complexes with Ap5A; Ap5A and MnCl2; Ap4A; ATP; and ATP.NaF.MgCl2. The aggregation pattern of molecules in the first four crystals is similar to that found in a majority of MsMutT1-NTP crystals. Substrate molecules occupy the primary binding site and ATP occupies a site at an intermolecular interface, in the first two. ATP occupies both the sites in the third and fourth crystal. The protein-ligand interactions observed in these crystal structures lead to an explanation of the molecular mechanism of hydrolysis of ApnA by MsMutT1. The fifth crystal exhibits a new packing arrangement. The structure of the complex provides an explanation for the fluoride inhibition of the activity of the enzyme. It would thus appear that MutT1 has a major role involving the hydrolysis of diadenosine polyphosphates, which could be elucidated at the molecular level.

Hydrolysis of diadenosine polyphosphates. Exploration of an additional role of Mycobacterium smegmatis MutT1.,Arif SM, Varshney U, Vijayan M J Struct Biol. 2017 Jul 10. pii: S1047-8477(17)30122-3. doi:, 10.1016/j.jsb.2017.07.002. PMID:28705712<ref>PMID:28705712</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5xd1" style="background-color:#fffaf0;"></div>

==See Also==
*[[7%2C8-dihydro-8-oxoguanine triphosphatase 3D structures|7%2C8-dihydro-8-oxoguanine triphosphatase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Mycolicibacterium smegmatis MC2 155]]
[[Category: Arif SM]]
[[Category: Varshney U]]
[[Category: Vijayan M]]