|
|
| (12 intermediate revisions by the same user not shown) |
| Line 1: |
Line 1: |
| [[Image:2aeu.gif|left|200px]]<br /><applet load="2aeu" size="350" color="white" frame="true" align="right" spinBox="true"
| |
| caption="2aeu, resolution 1.70Å" />
| |
| '''MJ0158, apo form'''<br />
| |
|
| |
|
| ==Overview== | | ==MJ0158, apo form== |
| Bacterial selenocysteine synthase converts seryl-tRNA(Sec) to selenocysteinyl-tRNA(Sec) for selenoprotein biosynthesis. The identity of this enzyme in archaea and eukaryotes is unknown. On the basis of sequence similarity, a conserved open reading frame has been annotated as a selenocysteine synthase gene in archaeal genomes. We have determined the crystal structure of the corresponding protein from Methanococcus jannaschii, MJ0158. The protein was found to be dimeric with a distinctive domain arrangement and an exposed active site, built from residues of the large domain of one protomer alone. The shape of the dimer is reminiscent of a substructure of the decameric Escherichia coli selenocysteine synthase seen in electron microscopic projections. However, biochemical analyses demonstrated that MJ0158 lacked affinity for E. coli seryl-tRNA(Sec) or M. jannaschii seryl-tRNA(Sec), and neither substrate was directly converted to selenocysteinyl-tRNA(Sec) by MJ0158 when supplied with selenophosphate. We then tested a hypothetical M. jannaschii O-phosphoseryl-tRNA(Sec) kinase and demonstrated that the enzyme converts seryl-tRNA(Sec) to O-phosphoseryl-tRNA(Sec) that could constitute an activated intermediate for selenocysteinyl-tRNA(Sec) production. MJ0158 also failed to convert O-phosphoseryl-tRNA(Sec) to selenocysteinyl-tRNA(Sec). In contrast, both archaeal and bacterial seryl-tRNA synthetases were able to charge both archaeal and bacterial tRNA(Sec) with serine, and E. coli selenocysteine synthase converted both types of seryl-tRNA(Sec) to selenocysteinyl-tRNA(Sec). These findings demonstrate that a number of factors from the selenoprotein biosynthesis machineries are cross-reactive between the bacterial and the archaeal systems but that MJ0158 either does not encode a selenocysteine synthase or requires additional factors for activity.
| | <StructureSection load='2aeu' size='340' side='right'caption='[[2aeu]], [[Resolution|resolution]] 1.70Å' scene=''> |
| | | == Structural highlights == |
| ==About this Structure== | | <table><tr><td colspan='2'>[[2aeu]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Methanocaldococcus_jannaschii Methanocaldococcus jannaschii]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2AEU OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2AEU FirstGlance]. <br> |
| 2AEU is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Methanocaldococcus_jannaschii Methanocaldococcus jannaschii] with <scene name='pdbligand=SO4:'>SO4</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2AEU OCA].
| | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.7Å</td></tr> |
| | | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr> |
| ==Reference== | | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2aeu FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2aeu OCA], [https://pdbe.org/2aeu PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2aeu RCSB], [https://www.ebi.ac.uk/pdbsum/2aeu PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2aeu ProSAT]</span></td></tr> |
| Structural and functional investigation of a putative archaeal selenocysteine synthase., Kaiser JT, Gromadski K, Rother M, Engelhardt H, Rodnina MV, Wahl MC, Biochemistry. 2005 Oct 11;44(40):13315-27. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=16201757 16201757]
| | </table> |
| | == Function == |
| | [https://www.uniprot.org/uniprot/Y158_METJA Y158_METJA] |
| | == Evolutionary Conservation == |
| | [[Image:Consurf_key_small.gif|200px|right]] |
| | Check<jmol> |
| | <jmolCheckbox> |
| | <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/ae/2aeu_consurf.spt"</scriptWhenChecked> |
| | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> |
| | <text>to colour the structure by Evolutionary Conservation</text> |
| | </jmolCheckbox> |
| | </jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=2aeu ConSurf]. |
| | <div style="clear:both"></div> |
| | __TOC__ |
| | </StructureSection> |
| | [[Category: Large Structures]] |
| [[Category: Methanocaldococcus jannaschii]] | | [[Category: Methanocaldococcus jannaschii]] |
| [[Category: Single protein]]
| | [[Category: Engelhardt H]] |
| [[Category: Engelhardt, H.]] | | [[Category: Gromadski K]] |
| [[Category: Gromadski, K.]] | | [[Category: Kaiser JT]] |
| [[Category: Kaiser, J T.]] | | [[Category: Rodnina MV]] |
| [[Category: Rodnina, M V.]] | | [[Category: Rother M]] |
| [[Category: Rother, M.]] | | [[Category: Wahl MC]] |
| [[Category: Wahl, M C.]] | |
| [[Category: SO4]]
| |
| [[Category: homo-oligomerization]]
| |
| [[Category: plp]]
| |
| [[Category: pyridoxal phosphate]]
| |
| [[Category: selenocysteine synthase]]
| |
| | |
| ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:26:42 2008''
| |