Related Experiment Videos
Iron environment in soybean lipoxygenase-1.
S Navaratnam1, M C Feiters, M Al-Hakim
1Research Division, North-East Wales Institute of Higher Education, Connah's Quay, Deeside, U.K.
Biochimica Et Biophysica Acta
|August 31, 1988
Summary
This study used Extended X-Ray Absorption Fine Structure (EXAFS) to analyze iron coordination in lipoxygenase. Researchers found approximately four imidazole ligands and other oxygen/nitrogen ligands, clarifying the enzyme's active site structure.
Area of Science:
- Biochemistry
- Structural Biology
- Biophysics
Background:
- Lipoxygenases are non-heme iron enzymes involved in various biological processes.
- Understanding the iron coordination site is crucial for elucidating enzyme function and mechanism.
Purpose of the Study:
- To determine the coordination environment of the non-heme iron(II) center in native lipoxygenase.
- To characterize the types and arrangement of ligands surrounding the iron atom.
Main Methods:
- Extended X-Ray Absorption Fine Structure (EXAFS) spectroscopy was employed to probe the local atomic structure around the iron center.
- Multiple scattering simulations were utilized to analyze the EXAFS data and estimate ligand numbers.
Main Results:
- The iron center is coordinated by 6 +/- 1 nitrogen and/or oxygen ligands at distances of 2.05-2.09 Å.
- EXAFS analysis, supported by simulations, suggests the presence of approximately 4 +/- 1 imidazole ligands.
- The remaining coordination sphere is proposed to consist of carboxylate oxygen ligands.
Conclusions:
- The study provides detailed insights into the iron coordination sphere of lipoxygenase.
- The findings contribute to a better understanding of the structural basis for lipoxygenase activity and substrate binding.