1e5a: Difference between revisions

Revision as of 14:40, 2 May 2008

STRUCTURE OF HUMAN TRANSTHYRETIN COMPLEXED WITH BROMOPHENOLS: A NEW MODE OF BINDING

OverviewOverview

The binding of two organohalogen substances, pentabromophenol (PBP) and 2,4,6-tribromophenol (TBP), to human transthyretin (TTR), a thyroid hormone transport protein, has been studied by in vitro competitive binding assays and by X-ray crystallography. Both compounds bind to TTR with high affinity, in competition with the natural ligand thyroxine (T(4)). The crystal structures of the TTR-PBP and TTR-TBP complexes show some unusual binding patterns for the ligands. They bind exclusively in the 'reversed' mode, with their hydroxyl group pointing towards the mouth of the binding channel and in planes approximately perpendicular to that adopted by the T(4) phenolic ring in a TTR-T(4) complex, a feature not observed before. The hydroxyl group in the ligands, which was previously thought to be a key ingredient for a strong binding to TTR, does not seem to play an important role in the binding of these compounds to TTR. In the TTR-PBP complex, it is primarily the halogens which interact with the TTR molecule and therefore must account for the strong affinity of binding. The interactions with the halogens are smaller in number in TTR-TBP and there is a decrease in affinity, even though the interaction with the hydroxyl group is stronger than that in the TTR-PBP complex.

About this StructureAbout this Structure

1E5A is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.

ReferenceReference

Structure of human transthyretin complexed with bromophenols: a new mode of binding., Ghosh M, Meerts IA, Cook A, Bergman A, Brouwer A, Johnson LN, Acta Crystallogr D Biol Crystallogr. 2000 Sep;56(Pt 9):1085-95. PMID:10957627 Page seeded by OCA on Fri May 2 14:40:48 2008

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OCA

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 [[Image:1e5a.gif|left|200px]]
- {{Structure
+<!--
-|PDB= 1e5a |SIZE=350|CAPTION= <scene name='initialview01'>1e5a</scene>, resolution 1.8&Aring;
+The line below this paragraph, containing "STRUCTURE_1e5a", creates the "Structure Box" on the page.
-|SITE= <scene name='pdbsite=1:Tbp+Binding+Site+Symmetry+Related+Subunit+Contributes+To+...'>1</scene> and <scene name='pdbsite=2:Tbp+Binding+Site+Symmetry+Related+Subunit+Contributes+To+...'>2</scene>
+You may change the PDB parameter (which sets the PDB file loaded into the applet)
-|LIGAND= <scene name='pdbligand=TBP:2,4,6-TRIBROMOPHENOL'>TBP</scene>
+or the SCENE parameter (which sets the initial scene displayed when the page is loaded),
-|ACTIVITY=
+or leave the SCENE parameter empty for the default display.
-|GENE=
+-->
-|DOMAIN=
+{{STRUCTURE_1e5a|  PDB=1e5a  |  SCENE=  }}
-|RELATEDENTRY=
-|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1e5a FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1e5a OCA], [http://www.ebi.ac.uk/pdbsum/1e5a PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1e5a RCSB]</span>
-}}
 '''STRUCTURE OF HUMAN TRANSTHYRETIN COMPLEXED WITH BROMOPHENOLS: A NEW MODE OF BINDING'''
@@ Line 31: / Line 28: @@
 [[Category: Johnson, L N.]]
 [[Category: Meerts, I A.T M.]]
-[[Category: bromophenol]]
+[[Category: Bromophenol]]
-[[Category: environmental pollutant]]
+[[Category: Environmental pollutant]]
-[[Category: transport(thyroxine)]]
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May  2 14:40:48 2008''
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 19:55:23 2008''