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Updated: Aug 9, 2026
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Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
How do the x-ray structure and the NMR structure of FMN-binding protein differ?
1Department of Life Science, Faculty of Science, Himeji Institute of Technology, 3-2-1 Kouto, Kamigori Ako-gun, Hyogo 678-1297, Japan.
Summary
The crystal structure of FMN-binding protein (FMN-bp) reveals a dimeric form, differing from its monomeric solution structure. This structural difference impacts FMN binding, particularly involving hydrophobic residues.
Area of Science:
- Structural Biology
- Biochemistry
- Crystallography
Background:
- FMN-binding protein (FMN-bp) is crucial for flavin metabolism.
- Previous studies suggested a monomeric structure in solution via NMR.
Purpose of the Study:
- To elucidate the three-dimensional crystal structure of FMN-bp from Desulfovibrio vulgaris Miyazaki F.
- To compare the crystal structure with the solution structure and understand FMN binding differences.
Main Methods:
- X-ray crystallography using the multiple isomorphous replacement method.
- Structure refinement to 1.3 Å resolution, achieving an R factor of 15.1%.
Main Results:
- The crystal structure reveals FMN-bp exists as a dimer, contrasting with the NMR-determined monomeric form.
- Significant structural differences (R.m.s. deviations > 2 Å) were observed between crystal and solution structures.
- Hydrophobic residues at the dimer interface, including Leu122, interact with the FMN o-xylene moiety, unlike in the solution structure.
Conclusions:
- The dimeric crystal structure provides new insights into FMN-bp's quaternary structure.
- Differences in structure explain variations in FMN binding, suggesting a role for hydrophobic interactions in the dimeric interface.
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