This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.

Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.


1nq9

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Current revision (13:28, 13 March 2024) (edit) (undo)
 
Line 22: Line 22:
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1nq9 ConSurf].
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1nq9 ConSurf].
<div style="clear:both"></div>
<div style="clear:both"></div>
-
<div style="background-color:#fffaf0;">
 
-
== Publication Abstract from PubMed ==
 
-
Antithrombin is activated as an inhibitor of the coagulation proteases through its specific interaction with a heparin pentasaccharide. The binding of heparin induces a global conformational change in antithrombin which results in the freeing of its reactive center loop for interaction with target proteases and a 1000-fold increase in heparin affinity. The allosteric mechanism by which the properties of antithrombin are altered by its interactions with the specific pentasaccharide sequence of heparin is of great interest to the medical and protein biochemistry communities. Heparin binding has previously been characterized as a two-step, three-state mechanism where, after an initial weak interaction, antithrombin undergoes a conformational change to its high-affinity state. Although the native and heparin-activated states have been determined through protein crystallography, the number and magnitude of conformational changes render problematic the task of determining which account for the improved heparin affinity and how the heparin binding region is linked to the expulsion of the reactive center loop. Here we present the structure of an intermediate pentasaccharide-bound conformation of antithrombin which has undergone all of the conformational changes associated with activation except loop expulsion and helix D elongation. We conclude that the basis of the high-affinity state is not improved interaction with the pentasaccharide but a lowering of the global free energy due to conformational changes elsewhere in antithrombin. We suggest a mechanism in which the role of helix D elongation is to lock antithrombin in the five-stranded fully activated conformation.
 
- 
-
Crystal structure of antithrombin in a heparin-bound intermediate state.,Johnson DJ, Huntington JA Biochemistry. 2003 Jul 29;42(29):8712-9. PMID:12873131<ref>PMID:12873131</ref>
 
- 
-
From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 
-
</div>
 
-
<div class="pdbe-citations 1nq9" style="background-color:#fffaf0;"></div>
 
==See Also==
==See Also==

Current revision

Crystal Structure of Antithrombin in the Pentasaccharide-Bound Intermediate State

PDB ID 1nq9

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1nq9"
Personal tools