1k0y

File:1k0y.gif

spinqualitylabelsall models 1k0y, resolution 1.87Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

X-ray Crystallographic Analyses of Symmetrical Allosteric Effectors of Hemoglobin. Compounds Designed to Link Primary and Secondary Binding Sites

OverviewOverview

The rational design and X-ray crystallographic analyses of two symmetrical, allosteric effectors of hemoglobin (Hb) are reported. Compound design was, directed by the previously solved co-crystal structure of one of the most, potent allosteric effectors of Hb, 2-[4-[(3,5-dichlorophenylcarbamoyl)-methyl]-phenoxy]-2-methylpropionic, acid (RSR4), which revealed two distinct binding sites for this compound, in the Hb central water cavity. The primary binding site has been observed, for all compounds of this structural class, which stabilize deoxy Hb by, engaging in inter-dimer contacts with three of the four protein subunits., Interactions at the secondary binding site of RSR4 occur primarily between, the beta(1) and beta(2) subunits and serve to further constrain the deoxy, state. Based on these observations, it was hypothesized that compounds, with the ability to simultaneously span and link both of these sites would, possess increased potency, but at a lower molar concentration than RSR4., Two symmetrical compounds were designed and synthesized based on this, hypothesis. The symmetrical effector approach was taken to minimize the, number of compound orientations needed to successfully bind at either of, the distinct allosteric sites. X-ray crystallographic analyses of these, two effectors in complex with Hb revealed that they successfully spanned, the RSR4 primary and secondary binding sites. However, the designed, compounds interacted with the secondary binding site in such a way that, intra-dimer, as opposed to inter-dimer, interactions were generated. In, agreement with these observations, in vitro evaluation of the symmetrical, effectors in Hb solution indicated that neither compound possessed the, potency of RSR4. A detailed analysis of symmetrical effector-Hb contacts, and comparisons with the binding contacts of RSR4 are discussed.

DiseaseDisease

Known diseases associated with this structure: Erythremias, alpha- OMIM:[141800], Erythremias, beta- OMIM:[141900], Erythrocytosis OMIM:[141850], HPFH, deletion type OMIM:[141900], Heinz body anemia OMIM:[141850], Heinz body anemias, alpha- OMIM:[141800], Heinz body anemias, beta- OMIM:[141900], Hemoglobin H disease OMIM:[141850], Hypochromic microcytic anemia OMIM:[141850], Methemoglobinemias, alpha- OMIM:[141800], Methemoglobinemias, beta- OMIM:[141900], Sickle cell anemia OMIM:[141900], Thalassemia, alpha- OMIM:[141850], Thalassemia-beta, dominant inclusion-body OMIM:[141900], Thalassemias, alpha- OMIM:[141800], Thalassemias, beta- OMIM:[141900]

About this StructureAbout this Structure

1K0Y is a Protein complex structure of sequences from Homo sapiens with SO4, HEM and CNO as ligands. Full crystallographic information is available from OCA.

ReferenceReference

X-ray crystallographic analyses of symmetrical allosteric effectors of hemoglobin: compounds designed to link primary and secondary binding sites., Safo MK, Boyiri T, Burnett JC, Danso-Danquah R, Moure CM, Joshi GS, Abraham DJ, Acta Crystallogr D Biol Crystallogr. 2002 Apr;58(Pt 4):634-44. Epub 2002, Mar 22. PMID:11914488

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