1za1: Difference between revisions

Revision as of 17:22, 3 May 2008

Structure of wild-type E. coli Aspartate Transcarbamoylase in the presence of CTP at 2.20 A resolution

OverviewOverview

X-ray structures of aspartate transcarbamoylase in the absence and presence of the first substrate carbamoyl phosphate are reported. These two structures in conjunction with in silico docking experiments provide snapshots of critical events in the function of the enzyme. The ordered substrate binding, observed experimentally, can now be structurally explained by a conformational change induced upon the binding of carbamoyl phosphate. This induced fit dramatically alters the electrostatics of the active site, creating a binding pocket for aspartate. Upon aspartate binding, a further change in electrostatics causes a second induced fit, the domain closure. This domain closure acts as a clamp that both facilitates catalysis by approximation and also initiates the global conformational change that manifests homotropic cooperativity.

About this StructureAbout this Structure

1ZA1 is a Protein complex structure of sequences from Escherichia coli. Full crystallographic information is available from OCA.

ReferenceReference

Structural basis for ordered substrate binding and cooperativity in aspartate transcarbamoylase., Wang J, Stieglitz KA, Cardia JP, Kantrowitz ER, Proc Natl Acad Sci U S A. 2005 Jun 21;102(25):8881-6. Epub 2005 Jun 10. PMID:15951418 Page seeded by OCA on Sat May 3 17:22:26 2008

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

OCA

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 [[Image:1za1.gif|left|200px]]
- {{Structure
+<!--
-|PDB= 1za1 |SIZE=350|CAPTION= <scene name='initialview01'>1za1</scene>, resolution 2.20&Aring;
+The line below this paragraph, containing "STRUCTURE_1za1", creates the "Structure Box" on the page.
-|SITE=
+You may change the PDB parameter (which sets the PDB file loaded into the applet)
-|LIGAND= <scene name='pdbligand=CTP:CYTIDINE-5&#39;-TRIPHOSPHATE'>CTP</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene>
+or the SCENE parameter (which sets the initial scene displayed when the page is loaded),
-|ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Aspartate_carbamoyltransferase Aspartate carbamoyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.1.3.2 2.1.3.2] </span>
+or leave the SCENE parameter empty for the default display.
-|GENE= PYRB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli]), PYRI ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli])
+-->
-|DOMAIN=
+{{STRUCTURE_1za1|  PDB=1za1  |  SCENE=  }}
-|RELATEDENTRY=[[1nbe|1NBE]], [[1za2|1ZA2]]
-|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1za1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1za1 OCA], [http://www.ebi.ac.uk/pdbsum/1za1 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1za1 RCSB]</span>
-}}
 '''Structure of wild-type E. coli Aspartate Transcarbamoylase in the presence of CTP at 2.20 A resolution'''
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 [[Category: Stieglitz, K A.]]
 [[Category: Wang, J.]]
-[[Category: cooperativity]]
+[[Category: Cooperativity]]
-[[Category: ordered substrate binding]]
+[[Category: Ordered substrate binding]]
-[[Category: x-ray crystallography]]
+[[Category: X-ray crystallography]]
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May  3 17:22:26 2008''
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Mar 31 01:32:53 2008''