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Updated: May 9, 2026
16:40
T-wave Ion Mobility-mass Spectrometry: Basic Experimental Procedures for Protein Complex Analysis
Published on: July 31, 2010
Solution structure and dynamics of human hemoglobin in the carbonmonoxy form
Jing-Song Fan1, Yu Zheng, Wing-Yiu Choy
1Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore.
Biochemistry
|August 2, 2013
Summary
Human hemoglobin
Area of Science:
- Biochemistry
- Structural Biology
- Biophysics
Background:
- Human adult hemoglobin (HbCO A) structure and dynamics are crucial for oxygen transport.
- Previous nuclear magnetic resonance (NMR) studies provided a basis for this refined analysis.
Purpose of the Study:
- To refine the solution structure of human adult carbonmonoxy hemoglobin (HbCO A) using advanced NMR techniques.
- To investigate the dynamics of HbCO A and the effects of inositol hexaphosphate (IHP) binding.
Main Methods:
- Refinement of NMR structure using stereospecifically assigned methyl groups and residual dipolar couplings.
- Inositol hexaphosphate (IHP) titration and docking to identify binding sites.
- Amide-water proton exchange and side chain methyl dynamics experiments.
Main Results:
- Solution quaternary structure resembles the X-ray R structure at low salt.
- Identified five potential IHP binding sites.
- Revealed a dynamic α1β2 interface crucial for conformational changes, with distinct dynamics at α1β1 and α1β2 interfaces.
- IHP binding induced subtle structural and dynamic changes, including millisecond-scale conformational changes likely due to dimer motion.
Conclusions:
- The α1β2 interface is highly dynamic, facilitating transitions between different hemoglobin forms in solution.
- IHP binding modulates hemoglobin dynamics and structure, potentially affecting oxygen affinity through altered dimer motion.
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