1oib: Difference between revisions

Revision as of 03:53, 3 May 2008

PHOSPHATE-BINDING PROTEIN MUTANT T141D

OverviewOverview

Electrostatic interactions are among the key forces determining the structure and function of proteins. These are exemplified in the liganded form of the receptor, a phosphate binding protein from Escherichia coli. The phosphate, completely dehydrated and buried in the receptor, is bound by 12 hydrogen bonds as well as a salt link with Arg 135. We have modulated the ionic attraction while preserving the hydrogen bonds by mutating Asp 137, also salt linked to Arg 135, to Asn, Gly or Thr. High-resolution crystallographic analysis revealed that Gly and Thr (but not Asn) mutant proteins have incorporated a more electronegative Cl- in place of the Asp carboxylate. That no dramatic effect on phosphate affinity was produced by these ionic perturbations indicates a major role for hydrogen bonds and other local dipoles in the binding and charge stabilization of ionic ligands.

About this StructureAbout this Structure

1OIB is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.

ReferenceReference

Modulation of a salt link does not affect binding of phosphate to its specific active transport receptor., Yao N, Ledvina PS, Choudhary A, Quiocho FA, Biochemistry. 1996 Feb 20;35(7):2079-85. PMID:8652549 Page seeded by OCA on Sat May 3 03:53:00 2008

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA

@@ Line 1: / Line 1: @@
 [[Image:1oib.gif|left|200px]]
- {{Structure
+<!--
-|PDB= 1oib |SIZE=350|CAPTION= <scene name='initialview01'>1oib</scene>, resolution 2.4&Aring;
+The line below this paragraph, containing "STRUCTURE_1oib", creates the "Structure Box" on the page.
-|SITE=
+You may change the PDB parameter (which sets the PDB file loaded into the applet)
-|LIGAND=
+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= PHOS ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli])
+-->
-|DOMAIN=
+{{STRUCTURE_1oib|  PDB=1oib  |  SCENE=  }}
-|RELATEDENTRY=
-|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1oib FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1oib OCA], [http://www.ebi.ac.uk/pdbsum/1oib PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1oib RCSB]</span>
-}}
 '''PHOSPHATE-BINDING PROTEIN MUTANT T141D'''
@@ Line 29: / Line 26: @@
 [[Category: Quiocho, F A.]]
 [[Category: Yao, N.]]
-[[Category: phosphate transport]]
+[[Category: Phosphate transport]]
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May  3 03:53:00 2008''
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 22:45:47 2008''