1nft: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image:1nft.gif|left|200px]] | [[Image:1nft.gif|left|200px]] | ||
<!-- | |||
The line below this paragraph, containing "STRUCTURE_1nft", creates the "Structure Box" on the page. | |||
You may change the PDB parameter (which sets the PDB file loaded into the applet) | |||
or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |||
or leave the SCENE parameter empty for the default display. | |||
--> | |||
| | {{STRUCTURE_1nft| PDB=1nft | SCENE= }} | ||
| | |||
}} | |||
'''OVOTRANSFERRIN, N-TERMINAL LOBE, IRON LOADED OPEN FORM''' | '''OVOTRANSFERRIN, N-TERMINAL LOBE, IRON LOADED OPEN FORM''' | ||
| Line 30: | Line 27: | ||
[[Category: Mizutani, K.]] | [[Category: Mizutani, K.]] | ||
[[Category: Yamashita, H.]] | [[Category: Yamashita, H.]] | ||
[[Category: | [[Category: Iron binding protein]] | ||
[[Category: | [[Category: Ovotransferrin]] | ||
[[Category: | [[Category: Transferrin]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 02:28:50 2008'' | |||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | |||
Revision as of 02:28, 3 May 2008
OVOTRANSFERRIN, N-TERMINAL LOBE, IRON LOADED OPEN FORM
OverviewOverview
Transferrins bind Fe3+ very tightly in a closed interdomain cleft by the coordination of four protein ligands (Asp60, Tyr92, Tyr191, and His250 in ovotransferrin N-lobe) and of a synergistic anion, physiologically bidentate CO32-. Upon Fe3+ uptake, transferrins undergo a large scale conformational transition: the apo structure with an opening of the interdomain cleft is transformed into the closed holo structure, implying initial Fe3+ binding in the open form. To solve the Fe3+-loaded, domain-opened structure, an ovotransferrin N-lobe crystal that had been grown as the apo form was soaked with Fe3+-nitrilotriacetate, and its structure was solved at 2.1 A resolution. The Fe3+-soaked form showed almost exactly the same overall open structure as the iron-free apo form. The electron density map unequivocally proved the presence of an iron atom with the coordination by the two protein ligands of Tyr92-OH and Tyr191-OH. Other Fe3+ coordination sites are occupied by a nitrilotriacetate anion, which is stabilized through the hydrogen bonds with the peptide NH groups of Ser122, Ala123, and Gly124 and a side chain group of Thr117. There is, however, no clear interaction between the nitrilotriacetate anion and the synergistic anion binding site, Arg121.
About this StructureAbout this Structure
1NFT is a Single protein structure of sequence from Gallus gallus. Full crystallographic information is available from OCA.
ReferenceReference
Alternative structural state of transferrin. The crystallographic analysis of iron-loaded but domain-opened ovotransferrin N-lobe., Mizutani K, Yamashita H, Kurokawa H, Mikami B, Hirose M, J Biol Chem. 1999 Apr 9;274(15):10190-4. PMID:10187803 Page seeded by OCA on Sat May 3 02:28:50 2008