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Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
The interaction between heme and protein in cytochrome c1
Biochimica Et Biophysica Acta
|January 13, 1983
Summary
Bovine cytochrome c1
Area of Science:
- Biochemistry
- Spectroscopy
- Protein Structure
Background:
- Cytochrome c1 is a crucial component of the electron transport chain.
- Understanding its heme ligation is vital for elucidating its function.
Purpose of the Study:
- To determine the axial ligands of heme in bovine cytochrome c1.
- To investigate the protein's conformation and heme exposure.
Main Methods:
- Optical spectroscopy at 77 K and room temperature.
- Solvent-perturbation spectroscopy.
- Electron paramagnetic resonance (EPR) spectroscopy.
Main Results:
- Native conformation of reduced cytochrome c1 shows beta-band splitting at 77 K.
- Heme exposure is sensitive to temperature and SH reagents.
- Methionine and cysteine were identified as the axial heme ligands.
- EPR studies confirmed low-spin heme iron in ferricytochrome c1.
Conclusions:
- Methionine and cysteine are the axial ligands of heme in bovine cytochrome c1.
- These ligands are critical for maintaining the protein's native structure and function.
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