1ajr

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:1ajr.jpg|left|200px]]
+
{{Seed}}
 +
[[Image:1ajr.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_1ajr| PDB=1ajr | SCENE= }}
{{STRUCTURE_1ajr| PDB=1ajr | SCENE= }}
-
'''REFINEMENT AND COMPARISON OF THE CRYSTAL STRUCTURES OF PIG CYTOSOLIC ASPARTATE AMINOTRANSFERASE AND ITS COMPLEX WITH 2-METHYLASPARTATE'''
+
===REFINEMENT AND COMPARISON OF THE CRYSTAL STRUCTURES OF PIG CYTOSOLIC ASPARTATE AMINOTRANSFERASE AND ITS COMPLEX WITH 2-METHYLASPARTATE===
-
==Overview==
+
<!--
-
Two high resolution crystal structures of cytosolic aspartate aminotransferase from pig heart provide additional insights into the stereochemical mechanism for ligand-induced conformational changes in this enzyme. Structures of the homodimeric native structure and its complex with the substrate analog 2-methylaspartate have been refined, respectively, with 1.74-A x-ray diffraction data to an R value of 0.170, and with 1.6-A data to an R value of 0.173. In the presence of 2-methylaspartate, one of the subunits (subunit 1) shows a ligand-induced conformational change that involves a large movement of the small domain (residues 12-49 and 327-412) to produce a "closed" conformation. No such transition is observed in the other subunit (subunit 2), because crystal lattice contacts lock it in an "open" conformation like that adopted by subunit 1 in the absence of substrate. By comparing the open and closed forms of cAspAT, we propose a stereochemical mechanism for the open-to-closed transition that involves the electrostatic neutralization of two active site arginine residues by the negative charges of the incoming substrate, a large change in the backbone (phi,psi) conformational angles of two key glycine residues, and the entropy-driven burial of a stretch of hydrophobic residues on the N-terminal helix. The calculated free energy for the burial of this "hydrophobic plug" appears to be sufficient to serve as the driving force for domain closure.
+
The line below this paragraph, {{ABSTRACT_PUBMED_9211866}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 9211866 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_9211866}}
==About this Structure==
==About this Structure==
Line 34: Line 38:
[[Category: Homodimer in the absence of ligand]]
[[Category: Homodimer in the absence of ligand]]
[[Category: Pig]]
[[Category: Pig]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 10:21:39 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jun 30 16:59:46 2008''

Revision as of 13:59, 30 June 2008

Image:1ajr.png

Template:STRUCTURE 1ajr

REFINEMENT AND COMPARISON OF THE CRYSTAL STRUCTURES OF PIG CYTOSOLIC ASPARTATE AMINOTRANSFERASE AND ITS COMPLEX WITH 2-METHYLASPARTATE

Template:ABSTRACT PUBMED 9211866

About this Structure

1AJR is a Single protein structure of sequence from Sus scrofa. Full crystallographic information is available from OCA.

Reference

Refinement and comparisons of the crystal structures of pig cytosolic aspartate aminotransferase and its complex with 2-methylaspartate., Rhee S, Silva MM, Hyde CC, Rogers PH, Metzler CM, Metzler DE, Arnone A, J Biol Chem. 1997 Jul 11;272(28):17293-302. PMID:9211866

Page seeded by OCA on Mon Jun 30 16:59:46 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1ajr"
Personal tools