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2gov
From Proteopedia
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| Gene: | Hebp1, Hbp (Mus musculus) | ||||||
| Domains: | SOUL | ||||||
| Resources: | FirstGlance, OCA, PDBsum, JenaLib, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Solution structure of Murine p22HBP
Overview
Murine p22HBP, a 22-kDa monomer originally identified as a cytosolic heme-binding protein ubiquitously expressed in various tissues, has 27% sequence identity to murine SOUL, a heme-binding hexamer specifically expressed in the retina. In contrast to murine SOUL, which binds one heme per subunit via coordination of the Fe(III)-heme to a histidine, murine p22HBP binds one heme molecule per subunit with no specific axial ligand coordination of the Fe(III)-heme. Using intrinsic protein fluorescence quenching, the values for the dissociation constants of p22HBP for hemin and protoporphyrin-IX were determined to be in the low nanomolar range. The three-dimensional structure of murine p22HBP, the first for a protein from the SOUL/HBP family, was determined by NMR methods to consist of a 9-stranded distorted beta-barrel flanked by two long alpha-helices. Although homologous domains have been found in three bacterial proteins, two of which are transcription factors, the fold determined for p22HBP corresponds to a novel alpha plus beta fold in a eukaryotic protein. Chemical shift mapping localized the tetrapyrrole binding site to a hydrophobic cleft formed by residues from helix alphaA and an extended loop. In an attempt to assess the structural basis for tetrapyrrole binding in the SOUL/HBP family, models for the p22HBP-protoporphyrin-IX complex and the SOUL protein were generated by manual docking and automated methods.
About this Structure
2GOV is a Single protein structure of sequence from Mus musculus. Full crystallographic information is available from OCA.
Reference
The first structure from the SOUL/HBP family of heme-binding proteins, murine P22HBP., Dias JS, Macedo AL, Ferreira GC, Peterson FC, Volkman BF, Goodfellow BJ, J Biol Chem. 2006 Oct 20;281(42):31553-61. Epub 2006 Aug 10. PMID:16905545
Page seeded by OCA on Wed Mar 26 06:27:10 2008
