5hbi
From Proteopedia
| Line 1: | Line 1: | ||
| - | [[Image:5hbi.gif|left|200px]] | + | [[Image:5hbi.gif|left|200px]] |
| - | + | ||
| - | '''SCAPHARCA DIMERIC HEMOGLOBIN, MUTANT T72I, CO-LIGANDED FORM''' | + | {{Structure |
| + | |PDB= 5hbi |SIZE=350|CAPTION= <scene name='initialview01'>5hbi</scene>, resolution 1.6Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene> and <scene name='pdbligand=CMO:CARBON MONOXIDE'>CMO</scene> | ||
| + | |ACTIVITY= | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''SCAPHARCA DIMERIC HEMOGLOBIN, MUTANT T72I, CO-LIGANDED FORM''' | ||
| + | |||
==Overview== | ==Overview== | ||
| Line 7: | Line 16: | ||
==About this Structure== | ==About this Structure== | ||
| - | 5HBI is a [ | + | 5HBI is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Scapharca_inaequivalvis Scapharca inaequivalvis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5HBI OCA]. |
==Reference== | ==Reference== | ||
| - | Mutational destabilization of the critical interface water cluster in Scapharca dimeric hemoglobin: structural basis for altered allosteric activity., Pardanani A, Gambacurta A, Ascoli F, Royer WE Jr, J Mol Biol. 1998 Dec 4;284(3):729-39. PMID:[http:// | + | Mutational destabilization of the critical interface water cluster in Scapharca dimeric hemoglobin: structural basis for altered allosteric activity., Pardanani A, Gambacurta A, Ascoli F, Royer WE Jr, J Mol Biol. 1998 Dec 4;284(3):729-39. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/9826511 9826511] |
[[Category: Scapharca inaequivalvis]] | [[Category: Scapharca inaequivalvis]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| Line 20: | Line 29: | ||
[[Category: respiratory protein]] | [[Category: respiratory protein]] | ||
| - | ''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 19:12:13 2008'' |
Revision as of 17:12, 20 March 2008
| |||||||
| , resolution 1.6Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | and | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
SCAPHARCA DIMERIC HEMOGLOBIN, MUTANT T72I, CO-LIGANDED FORM
Overview
A cluster of interface ordered water molecules has been proposed to act as a key mediator of intersubunit communication in the homodimeric hemoglobin of Scapharca inaequivalvis. Mutations of Thr72 to Val and Ile, which lack the hydroxyl group to hydrogen bond the deoxy interface water molecules, result in sharply altered functional properties. We have determined the high resolution (1.6-1. 8 A) crystal structures of these two mutants in both the deoxygenated and CO-liganded states. These structures show minimal protein structural changes relative to the same native derivatives, despite greater than 40-fold increases in oxygen affinity. In the deoxy state of both mutants two water molecules at the periphery of the water cluster are lost, and the remaining cluster water molecules are destabilized. The CO-liganded structures show key differences between the two mutants including a more optimal interface packing involving Ile72 that acts to stabilize its high affinity (R) state. This additional stabilization allows rationalization of its lowered cooperativity within the context of a two-state model. These studies support a key role of ordered water in cooperative functioning and illustrate how subtle structural alterations can result in significantly altered functional properties in an allosteric molecule.
About this Structure
5HBI is a Single protein structure of sequence from Scapharca inaequivalvis. Full crystallographic information is available from OCA.
Reference
Mutational destabilization of the critical interface water cluster in Scapharca dimeric hemoglobin: structural basis for altered allosteric activity., Pardanani A, Gambacurta A, Ascoli F, Royer WE Jr, J Mol Biol. 1998 Dec 4;284(3):729-39. PMID:9826511
Page seeded by OCA on Thu Mar 20 19:12:13 2008
