2r4z
From Proteopedia
| Line 1: | Line 1: | ||
[[Image:2r4z.jpg|left|200px]] | [[Image:2r4z.jpg|left|200px]] | ||
| - | + | <!-- | |
| - | + | The line below this paragraph, containing "STRUCTURE_2r4z", 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_2r4z| PDB=2r4z | SCENE= }} | |
| - | + | ||
| - | + | ||
| - | }} | + | |
'''Ligand Migration and Binding in The Dimeric Hemoglobin of Scapharca Inaequivalvis: Structure of I25W with CO''' | '''Ligand Migration and Binding in The Dimeric Hemoglobin of Scapharca Inaequivalvis: Structure of I25W with CO''' | ||
| Line 30: | Line 27: | ||
[[Category: Nienhaus, K.]] | [[Category: Nienhaus, K.]] | ||
[[Category: Palladino, P.]] | [[Category: Palladino, P.]] | ||
| - | [[Category: | + | [[Category: Allostery]] |
| - | [[Category: | + | [[Category: Cytoplasm]] |
| - | [[Category: | + | [[Category: Heme]] |
| - | [[Category: | + | [[Category: Iron]] |
| - | [[Category: | + | [[Category: Metal-binding]] |
| - | [[Category: | + | [[Category: Oxygen affinity]] |
| - | [[Category: | + | [[Category: Oxygen binding]] |
| - | [[Category: | + | [[Category: Oxygen storage/transport]] |
| - | [[Category: | + | [[Category: Oxygen transport]] |
| - | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun May 4 16:15:21 2008'' | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
Revision as of 13:15, 4 May 2008
Ligand Migration and Binding in The Dimeric Hemoglobin of Scapharca Inaequivalvis: Structure of I25W with CO
Overview
Using Fourier transform infrared (FTIR) spectroscopy combined with temperature derivative spectroscopy (TDS) at cryogenic temperatures, we have studied CO binding to the heme and CO migration among cavities in the interior of the dimeric hemoglobin of Scapharca inaequivalvis (HbI) after photodissociation. By combining these studies with X-ray crystallography, three transient ligand docking sites were identified: a primary docking site B in close vicinity to the heme iron, and two secondary docking sites C and D corresponding to the Xe4 and Xe2 cavities of myoglobin. To assess the relevance of these findings for physiological binding, we also performed flash photolysis experiments on HbICO at room temperature and equilibrium binding studies with dioxygen. Our results show that the Xe4 and Xe2 cavities serve as transient docking sites for unbound ligands in the protein, but not as way stations on the entry/exit pathway. For HbI, the so-called histidine gate mechanism proposed for other globins appears as a plausible entry/exit route as well.
About this Structure
2R4Z is a Single protein structure of sequence from Scapharca inaequivalvis. Full crystallographic information is available from OCA.
Reference
Ligand migration and binding in the dimeric hemoglobin of Scapharca inaequivalvis., Nienhaus K, Knapp JE, Palladino P, Royer WE Jr, Nienhaus GU, Biochemistry. 2007 Dec 11;46(49):14018-31. Epub 2007 Nov 15. PMID:18001141 Page seeded by OCA on Sun May 4 16:15:21 2008
