1moh
From Proteopedia
(New page: 200px<br /> <applet load="1moh" size="450" color="white" frame="true" align="right" spinBox="true" caption="1moh, resolution 1.9Å" /> '''FERRIC MONOMERIC HEM...) |
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| - | [[Image:1moh.gif|left|200px]]<br /> | + | [[Image:1moh.gif|left|200px]]<br /><applet load="1moh" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="1moh" size=" | + | |
caption="1moh, resolution 1.9Å" /> | caption="1moh, resolution 1.9Å" /> | ||
'''FERRIC MONOMERIC HEMOGLOBIN I (HB I)'''<br /> | '''FERRIC MONOMERIC HEMOGLOBIN I (HB I)'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The X-ray crystal structure of the sulfide derivative of ferric Lucina | + | The X-ray crystal structure of the sulfide derivative of ferric Lucina pectinata hemoglobin component I (HbI) has been determined at 1.9 A resolution (R-factor 0.186). The heme pocket structural organization of HbI is in keeping with its ligand binding properties. The fast sulfide association rate constant can be related to the presence of Gln(64)E7, as the heme distal residue, together with the protein structural properties in the CD-E distal region. Moreover, the very high sulfide affinity for HbI is reflected by the exceptionally slow ligand dissociation rate. The stabilization of the heme-bound sulfide molecule is achieved through hydrogen bonding to Gln(64)E7, as well as by finely tuned aromatic-electrostatic interactions with the clustered residues Phe(29)B10, Phe(43)CD1 and Phe(68)E11. Such a peculiar arrangement of phenylalanyl residues at the distal ligand binding site has not been observed before in the globin family, and is unique to HbI, a protein functionally devoted to sulfide transport. |
==About this Structure== | ==About this Structure== | ||
| - | 1MOH is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Lucina_pectinata Lucina pectinata] with HEM and H2S as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1MOH is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Lucina_pectinata Lucina pectinata] with <scene name='pdbligand=HEM:'>HEM</scene> and <scene name='pdbligand=H2S:'>H2S</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1MOH OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Bolognesi, M.]] | [[Category: Bolognesi, M.]] | ||
[[Category: Rizzi, M.]] | [[Category: Rizzi, M.]] | ||
| - | [[Category: Wittenberg, J | + | [[Category: Wittenberg, J B.]] |
[[Category: H2S]] | [[Category: H2S]] | ||
[[Category: HEM]] | [[Category: HEM]] | ||
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[[Category: sulfide transport]] | [[Category: sulfide transport]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:57:22 2008'' |
Revision as of 11:57, 21 February 2008
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FERRIC MONOMERIC HEMOGLOBIN I (HB I)
Overview
The X-ray crystal structure of the sulfide derivative of ferric Lucina pectinata hemoglobin component I (HbI) has been determined at 1.9 A resolution (R-factor 0.186). The heme pocket structural organization of HbI is in keeping with its ligand binding properties. The fast sulfide association rate constant can be related to the presence of Gln(64)E7, as the heme distal residue, together with the protein structural properties in the CD-E distal region. Moreover, the very high sulfide affinity for HbI is reflected by the exceptionally slow ligand dissociation rate. The stabilization of the heme-bound sulfide molecule is achieved through hydrogen bonding to Gln(64)E7, as well as by finely tuned aromatic-electrostatic interactions with the clustered residues Phe(29)B10, Phe(43)CD1 and Phe(68)E11. Such a peculiar arrangement of phenylalanyl residues at the distal ligand binding site has not been observed before in the globin family, and is unique to HbI, a protein functionally devoted to sulfide transport.
About this Structure
1MOH is a Single protein structure of sequence from Lucina pectinata with and as ligands. Full crystallographic information is available from OCA.
Reference
Structural bases for sulfide recognition in Lucina pectinata hemoglobin I., Rizzi M, Wittenberg JB, Coda A, Ascenzi P, Bolognesi M, J Mol Biol. 1996 Apr 26;258(1):1-5. PMID:8613980
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