3p03: Difference between revisions

<StructureSection load='3p03' size='340' side='right' caption='[[3p03]], [[Resolution|resolution]] 3.35&Aring;' scene=''>

<table><tr><td colspan='2'>[[3p03]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/"micrococcus_glutamicus"_kinoshita_et_al._1958 "micrococcus glutamicus" kinoshita et al. 1958]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3P03 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3P03 FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CHT:CHOLINE+ION'>CHT</scene></td></tr>

<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">betP, Cgl0892, cg1016 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1718 "Micrococcus glutamicus" Kinoshita et al. 1958])</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=3p03 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3p03 OCA], [http://pdbe.org/3p03 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3p03 RCSB], [http://www.ebi.ac.uk/pdbsum/3p03 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3p03 ProSAT]</span></td></tr>

[[http://www.uniprot.org/uniprot/BETP_CORGL BETP_CORGL]] High-affinity uptake of glycine betaine (By similarity).

BetP is an Na(+)-coupled betaine-specific transporter of the betaine-choline-carnitine (BCC) transporter family involved in the response to hyperosmotic stress. The crystal structure of BetP revealed an overall fold of two inverted structurally related repeats (LeuT-fold) that BetP shares with other sequence-unrelated Na(+)-coupled symporters. Numerous structures of LeuT-fold transporters in distinct conformational states have contributed substantially to our understanding of the alternating access mechanism of transport. Nevertheless, coupling of substrate and co-transported ion fluxes has not been structurally corroborated to the same extent. We converted BetP by a single-point mutation-glycine to aspartate-into an H(+)-coupled choline-specific transporter and solved the crystal structure of this mutant in complex with choline. The structure of BetP-G153D demonstrates a new inward-facing open conformation for BetP. Choline binding to a location close to the second, low-affinity sodium-binding site (Na2) of LeuT-fold transporters is facilitated by the introduced aspartate. Our data confirm the importance of a cation-binding site in BetP, playing a key role in a proposed molecular mechanism of Na(+) and H(+) coupling in BCC transporters.

 

== References ==

[[Category: Micrococcus glutamicus kinoshita et al. 1958]]

[[Category: Perez, C]]

[[Category: Ressl, S]]

[[Category: Ziegler, Z]]

[[Category: Secondary transporter]]

[[Category: Transport protein]]