View source for 1col

==REFINED STRUCTURE OF THE PORE-FORMING DOMAIN OF COLICIN A AT 2.4 ANGSTROMS RESOLUTION==
<StructureSection load='1col' size='340' side='right' caption='[[1col]], [[Resolution|resolution]] 2.40&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1col]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1COL OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1COL FirstGlance]. <br>
</td></tr><tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1col FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1col OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1col RCSB], [http://www.ebi.ac.uk/pdbsum/1col PDBsum]</span></td></tr>
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== 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/co/1col_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/chain_selection.php?pdb_ID=2ata ConSurf].
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== Publication Abstract from PubMed ==
The E1 subgroup (E1, A, B, IA, IB, K and N) of anti-bacterial toxins called colicins is known to form voltage-dependent channels in lipid bilayers. The crystal structure of the pore-forming domain of colicin A from Escherichia coli has been refined to the diffraction limit of the crystals at 2.4 A resolution by means of molecular dynamics and restrained least-squares methods to a conventional R-factor of 0.18 for all data between 6.0 and 2.4 A resolution. The polypeptide chain of 204 amino acid residues consists of ten alpha-helices organized in a three-layer structure. The helices range in length from 9 to 23 residues with an average length of 125 residues. The packing arrangement of the helices has been analysed; the packing is different from that observed in four-helix bundle proteins. The sites of 83 water molecules have been located and refined. Analysis of the structure provides insights into the mechanism of formation of a voltage-gated channel by the protein. Although it is proposed that substantial tertiary structural changes occur during membrane insertion, the secondary structural elements remain conserved. This idea has been proposed recently for a number of other protein-membrane events and thus may have more general applicability.

Refined structure of the pore-forming domain of colicin A at 2.4 A resolution.,Parker MW, Postma JP, Pattus F, Tucker AD, Tsernoglou D J Mol Biol. 1992 Apr 5;224(3):639-57. PMID:1373773<ref>PMID:1373773</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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==See Also==
*[[Colicin|Colicin]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Parker, M W.]]
[[Category: Pattus, F.]]
[[Category: Postma, J P.M.]]
[[Category: Tsernoglou, D.]]
[[Category: Tucker, A D.]]
[[Category: Antibacterial protein]]