4sdh
From Proteopedia
| Line 1: | Line 1: | ||
| - | [[Image:4sdh.jpg|left|200px]] | + | [[Image:4sdh.jpg|left|200px]] |
| - | + | ||
| - | '''HIGH RESOLUTION CRYSTALLOGRAPHIC ANALYSIS OF A COOPERATIVE DIMERIC HEMOGLOBIN''' | + | {{Structure |
| + | |PDB= 4sdh |SIZE=350|CAPTION= <scene name='initialview01'>4sdh</scene>, resolution 1.6Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=HEM:PROTOPORPHYRIN IX CONTAINING FE'>HEM</scene> | ||
| + | |ACTIVITY= | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''HIGH RESOLUTION CRYSTALLOGRAPHIC ANALYSIS OF A COOPERATIVE DIMERIC HEMOGLOBIN''' | ||
| + | |||
==Overview== | ==Overview== | ||
| Line 7: | Line 16: | ||
==About this Structure== | ==About this Structure== | ||
| - | 4SDH is a [ | + | 4SDH is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Scapharca_inaequivalvis Scapharca inaequivalvis]. This structure supersedes the now removed PDB entry 2SDH. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4SDH OCA]. |
==Reference== | ==Reference== | ||
| - | High-resolution crystallographic analysis of a co-operative dimeric hemoglobin., Royer WE Jr, J Mol Biol. 1994 Jan 14;235(2):657-81. PMID:[http:// | + | High-resolution crystallographic analysis of a co-operative dimeric hemoglobin., Royer WE Jr, J Mol Biol. 1994 Jan 14;235(2):657-81. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/8289287 8289287] |
[[Category: Scapharca inaequivalvis]] | [[Category: Scapharca inaequivalvis]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| Line 17: | Line 26: | ||
[[Category: oxygen transport]] | [[Category: oxygen transport]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 19:10:59 2008'' |
Revision as of 17:11, 20 March 2008
| |||||||
| , resolution 1.6Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | |||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
HIGH RESOLUTION CRYSTALLOGRAPHIC ANALYSIS OF A COOPERATIVE DIMERIC HEMOGLOBIN
Overview
High-resolution crystal structures of the co-operative dimeric hemoglobin from the blood clam Scapharca inaequivalvis have been determined in the unliganded (deoxy) and carbon monoxide (CO) liganded states. The deoxy structure has been refined at 1.6 A resolution to an R-factor of 0.158 and the CO structure has been refined at 1.4 A resolution to an R-factor of 0.159. These structures reveal details of the structural transitions involved in co-operative ligand binding that involve only a minor rotation of subunits but very striking tertiary changes at the interface. A small number of residues in the F-helix appear to mediate co-operativity in this simple hemoglobin. The oxygen affinity of each subunit appears to be largely dictated by the disposition of phenylalanine 97, whose side-chain packs in the heme pocket in the deoxy state but is extruded towards the interface in the CO-liganded structure. Direct involvement of the ligand-binding heme group is a novel feature of the subunit interface and appears important for intersubunit communication. Ligation alters the conformation of the heme propionate groups along with two interacting residues from the symmetry-related subunit. These two residues, lysine 96 and asparagine 100, link the heme of one subunit with the F-helix of the second subunit in such a way as to influence the ligand affinity of that subunit. The interface is highly hydrated by well-ordered water molecules that are likely to be important in the stabilization of the two structures.
About this Structure
4SDH is a Single protein structure of sequence from Scapharca inaequivalvis. This structure supersedes the now removed PDB entry 2SDH. Full crystallographic information is available from OCA.
Reference
High-resolution crystallographic analysis of a co-operative dimeric hemoglobin., Royer WE Jr, J Mol Biol. 1994 Jan 14;235(2):657-81. PMID:8289287
Page seeded by OCA on Thu Mar 20 19:10:59 2008
