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1y01
From Proteopedia
| 1y01, resolution 2.80Å () | |||||||||
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| Ligands: | , , | ||||||||
| Gene: | AHSP, EDRF, ERAF (Homo sapiens), HBA1 (Homo sapiens) | ||||||||
| Domains: | AHSP, globin | ||||||||
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||
Contents |
Crystal structure of AHSP bound to Fe(II) alpha-hemoglobin
Hemoglobin A (HbA), the oxygen delivery system in humans, comprises two alpha and two beta subunits. Free alpha-hemoglobin (alphaHb) is unstable, and its precipitation contributes to the pathophysiology of beta thalassemia. In erythrocytes, the alpha-hemoglobin stabilizing protein (AHSP) binds alphaHb and inhibits its precipitation. The crystal structure of AHSP bound to Fe(II)-alphaHb reveals that AHSP specifically recognizes the G and H helices of alphaHb through a hydrophobic interface that largely recapitulates the alpha1-beta1 interface of hemoglobin. The AHSP-alphaHb interactions are extensive but suboptimal, explaining why beta-hemoglobin can competitively displace AHSP to form HbA. Remarkably, the Fe(II)-heme group in AHSP bound alphaHb is coordinated by the distal but not the proximal histidine. Importantly, binding to AHSP facilitates the conversion of oxy-alphaHb to a deoxygenated, oxidized [Fe(III)], nonreactive form in which all six coordinate positions are occupied. These observations reveal the molecular mechanisms by which AHSP stabilizes free alphaHb.
Molecular mechanism of AHSP-mediated stabilization of alpha-hemoglobin., Feng L, Gell DA, Zhou S, Gu L, Kong Y, Li J, Hu M, Yan N, Lee C, Rich AM, Armstrong RS, Lay PA, Gow AJ, Weiss MJ, Mackay JP, Shi Y, Cell. 2004 Nov 24;119(5):629-40. PMID:15550245
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
Disease
Known disease associated with this structure: Erythremias, alpha- OMIM:[141800], Heinz body anemias, alpha- OMIM:[141800], Methemoglobinemias, alpha- OMIM:[141800], Thalassemias, alpha- OMIM:[141800]
About this Structure
1Y01 is a 2 chains structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
Reference
- Feng L, Gell DA, Zhou S, Gu L, Kong Y, Li J, Hu M, Yan N, Lee C, Rich AM, Armstrong RS, Lay PA, Gow AJ, Weiss MJ, Mackay JP, Shi Y. Molecular mechanism of AHSP-mediated stabilization of alpha-hemoglobin. Cell. 2004 Nov 24;119(5):629-40. PMID:15550245 doi:10.1016/j.cell.2004.11.025
Page seeded by OCA on Mon Feb 16 19:04:10 2009
