View source for 1etk

==THE CRYSTAL STRUCTURE OF E. COLI FIS MUTANT Q68A==
<StructureSection load='1etk' size='340' side='right' caption='[[1etk]], [[Resolution|resolution]] 2.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1etk]] 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=1ETK OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1ETK FirstGlance]. <br>
</td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3fis|3fis]], [[1fip|1fip]], [[1f36|1f36]], [[1eto|1eto]], [[1etq|1etq]], [[1etv|1etv]], [[1etw|1etw]], [[1etx|1etx]], [[1ety|1ety]]</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=1etk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1etk OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1etk RCSB], [http://www.ebi.ac.uk/pdbsum/1etk PDBsum]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/FIS_ECOLI FIS_ECOLI]] Activates ribosomal RNA transcription, as well other genes. Plays a direct role in upstream activation of rRNA promoters. Binds to a recombinational enhancer sequence that is required to stimulate hin-mediated DNA inversion. Prevents initiation of DNA replication from oriC.<ref>PMID:2209559</ref> <ref>PMID:8836178</ref>  
== 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/et/1etk_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 Fis protein regulates gene expression in Escherichia coli by activating or repressing transcription of a variety of genes. Fis can activate transcription when bound to DNA upstream of the RNA-polymerase-binding site, such as in the rrnB P1 promoter, or when bound to a site overlapping the -35 RNA polymerase binding site, such as in the proP P2 promoter. It has been suggested that transcriptional activation in both promoters results from interactions between specific amino acids within a turn connecting the B and C helices (the BC turn) in Fis and the C-terminal domain of the alpha-subunit of RNA polymerase (alphaCTD of RNAP). Here, crystal structures of six Fis BC turn mutants with different transcriptional activation properties, Q68A, R71Y, R71L, G72A, G72D and Q74A, were determined at 1.9 to 2.8 A resolution. Two of these mutants, R71Y and R71L, crystallized in unit cells which are different from that of wild-type Fis, and the structure of R71L offers the most complete Fis model to date in that the extended structure of the N-terminal region is revealed. The BC turn in all of these mutant structures remains in a nearly identical gamma gamma beta-turn conformation as present in wild-type Fis. Analyses of the molecular surfaces of the transactivation region of the mutants suggest that several residues in or near the BC turn, including Gln68, Arg71, Gly72 and Gln74, form a ridge that could contact the alphaCTD of RNAP on one side. The structures and biochemical properties of the mutants suggest that Arg71 is the most critical residue for contacting RNAP within this ridge and that the glycine at position 72 helps to stabilize the structure.

Structural analysis of the transcriptional activation on Fis: crystal structures of six Fis mutants with different activation properties.,Cheng YS, Yang WZ, Johnson RC, Yuan HS J Mol Biol. 2000 Oct 6;302(5):1139-51. PMID:11183780<ref>PMID:11183780</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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==See Also==
*[[FIS protein|FIS protein]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Cheng, Y S]]
[[Category: Johnson, R C]]
[[Category: Yang, W Z]]
[[Category: Yuan, H S]]
[[Category: Dna-binding protein]]
[[Category: Transcription activator]]
[[Category: Transcriptional activation region]]