AI Article Synopsis
- The study conducted docking and 500-ps molecular dynamics simulations of R-state human adult hemoglobin (HbA) with various effectors to understand their interactions with oxygenated hemoglobin.
- The results indicated that like the T-state hemoglobin, the R-state effector binding sites are in the central cavity, but their locations vary based on the anionic character of the effector.
- The models created are the first to detail the molecular interactions between R-state HbA and the heterotropic effectors, providing new insights into these biochemical processes.
Article Abstract
We performed a docking study followed by a 500-ps molecular dynamics simulation of R-state human adult hemoglobin (HbA) complexed to different heterotropic effectors [2,3-diphosphoglycerate (DPG), inositol hexaphosphate (IHP), and 2-[4-[(3,5-dichlorophenylcarbamoyl)-]methyl]-phenoxy]-2-methylpropionic acid (RSR13)) to propose a molecular basis for recently reported interactions of effectors with oxygenated hemoglobin. The simulations were carried out with counterions and explicit solvation. As reported for T-state HbA, the effector binding sites are also located in the central cavity of the R-state and differ depending on effector anionic character. DPG and IHP bind between the alpha-subunits and the RSR13 site spans the alpha1-, alpha2- and beta2-subunits. The generated models provide the first report of the molecular details of R-state HbA bound to heterotropic effectors.
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| http://dx.doi.org/10.1016/j.febslet.2004.12.033 | DOI Listing |
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