1zcd

<StructureSection load='1zcd' size='340' side='right' caption='[[1zcd]], [[Resolution|resolution]] 3.45&Aring;' scene=''>

<table><tr><td colspan='2'>[[1zcd]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. The December 2011 RCSB PDB [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month] feature on ''Complex I'' by David Goodsell is [http://dx.doi.org/10.2210/rcsb_pdb/mom_2011_12 10.2210/rcsb_pdb/mom_2011_12]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1ZCD OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1ZCD FirstGlance]. <br>

</td></tr><tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">nhaA ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli])</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=1zcd FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1zcd OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1zcd RCSB], [http://www.ebi.ac.uk/pdbsum/1zcd PDBsum]</span></td></tr>

[[http://www.uniprot.org/uniprot/NHAA_ECOLI NHAA_ECOLI]] Na(+)/H(+) antiporter that extrudes sodium in exchange for external protons. Catalyzes the exchange of 2 H(+) per Na(+). Can mediate sodium uptake when a transmembrane pH gradient is applied. Active at alkaline pH. Activity is strongly down-regulated below pH 6.5.<ref>PMID:1645730</ref>

<scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/zc/1zcd_consurf.spt"</scriptWhenChecked>

</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 control by Na+/H+ antiporters of sodium/proton concentration and cell volume is crucial for the viability of all cells. Adaptation to high salinity and/or extreme pH in plants and bacteria or in human heart muscles requires the action of Na+/H+ antiporters. Their activity is tightly controlled by pH. Here we present the crystal structure of pH-downregulated NhaA, the main antiporter of Escherichia coli and many enterobacteria. A negatively charged ion funnel opens to the cytoplasm and ends in the middle of the membrane at the putative ion-binding site. There, a unique assembly of two pairs of short helices connected by crossed, extended chains creates a balanced electrostatic environment. We propose that the binding of charged substrates causes an electric imbalance, inducing movements, that permit a rapid alternating-access mechanism. This ion-exchange machinery is regulated by a conformational change elicited by a pH signal perceived at the entry to the cytoplasmic funnel.

Structure of a Na+/H+ antiporter and insights into mechanism of action and regulation by pH.,Hunte C, Screpanti E, Venturi M, Rimon A, Padan E, Michel H Nature. 2005 Jun 30;435(7046):1197-202. PMID:15988517<ref>PMID:15988517</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

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[[Category: Hunte, C]]

[[Category: Michel, H]]

[[Category: Padan, E]]

[[Category: Rimon, A]]

[[Category: Screpanti, E]]

[[Category: Venturi, M]]

[[Category: Membrane protein]]