2ae9: Difference between revisions
No edit summary |
No edit summary |
||
(12 intermediate revisions by the same user not shown) | |||
Line 1: | Line 1: | ||
==Solution Structure of the theta subunit of DNA polymerase III from E. coli== | |||
<StructureSection load='2ae9' size='340' side='right'caption='[[2ae9]]' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[2ae9]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2AE9 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2AE9 FirstGlance]. <br> | |||
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR</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=2ae9 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ae9 OCA], [https://pdbe.org/2ae9 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2ae9 RCSB], [https://www.ebi.ac.uk/pdbsum/2ae9 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2ae9 ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/HOLE_ECOLI HOLE_ECOLI] DNA polymerase III is a complex, multichain enzyme responsible for most of the replicative synthesis in bacteria. This DNA polymerase also exhibits 3' to 5' exonuclease activity. The exact function of the theta subunit is unknown. | |||
== 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/2ae9_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=2ae9 ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
The catalytic core of Escherichia coli DNA polymerase III holoenzyme contains three subunits: alpha, epsilon, and theta. The alpha subunit contains the polymerase, and the epsilon subunit contains the exonucleolytic proofreading function. The small (8-kDa) theta subunit binds only to epsilon. Its function is not well understood, although it was shown to exert a small stabilizing effect on the epsilon proofreading function. In order to help elucidate its function, we undertook a determination of its solution structure. In aqueous solution, theta yielded poor-quality nuclear magnetic resonance spectra, presumably due to conformational exchange and/or protein aggregation. Based on our recently determined structure of the theta homolog from bacteriophage P1, named HOT, we constructed a homology model of theta. This model suggested that the unfavorable behavior of theta might arise from exposed hydrophobic residues, particularly toward the end of alpha-helix 3. In gel filtration studies, theta elutes later than expected, indicating that aggregation is potentially responsible for these problems. To address this issue, we recorded 1H-15N heteronuclear single quantum correlation (HSQC) spectra in water-alcohol mixed solvents and observed substantially improved dispersion and uniformity of peak intensities, facilitating a structural determination under these conditions. The structure of theta in 60/40 (vol/vol) water-methanol is similar to that of HOT but differs significantly from a previously reported theta structure. The new theta structure is expected to provide additional insight into its physiological role and its effect on the epsilon proofreading subunit. | |||
Nuclear magnetic resonance solution structure of the Escherichia coli DNA polymerase III theta subunit.,Mueller GA, Kirby TW, DeRose EF, Li D, Schaaper RM, London RE J Bacteriol. 2005 Oct;187(20):7081-9. PMID:16199579<ref>PMID:16199579</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 2ae9" style="background-color:#fffaf0;"></div> | |||
== | ==See Also== | ||
*[[DNA polymerase 3D structures|DNA polymerase 3D structures]] | |||
== References == | |||
== | <references/> | ||
__TOC__ | |||
</StructureSection> | |||
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: | [[Category: Large Structures]] | ||
[[Category: Derose | [[Category: Derose EF]] | ||
[[Category: Kirby | [[Category: Kirby TW]] | ||
[[Category: Li | [[Category: Li D]] | ||
[[Category: London | [[Category: London RE]] | ||
[[Category: Mueller | [[Category: Mueller GA]] | ||
[[Category: Schaaper | [[Category: Schaaper RM]] | ||