1moh
From Proteopedia
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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 HEM and H2S 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
Page seeded by OCA on Thu Nov 8 13:13:30 2007
