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TransFLP — A Method to Genetically Modify Vibrio cholerae Based on Natural Transformation and FLP-recombination
Published on: October 8, 2012
A single-residue mutation destabilizes Vibrio harveyi flavin reductase FRP dimer
Navneet Jawanda1, Jerry Ebalunode, Alexey Gribenko
1Department of Biology and Biochemistry, University of Houston, 4800 Calhoun, Houston, TX 77204-5001, USA.
Archives of Biochemistry and Biophysics
|February 26, 2008
Summary
Vibrio harveyi flavin reductase (FRP) subunit interactions were investigated. A specific mutation (E99K) significantly enhanced subunit dissociation, revealing a critical role for residue E99 in FRP dimer formation.
Area of Science:
- Biochemistry
- Molecular Biology
- Enzymology
Background:
- Vibrio harveyi flavin reductase (FRP) exhibits a monomer-dimer equilibrium crucial for luciferase complex formation.
- Understanding FRP subunit interactions is key to elucidating its regulatory mechanisms.
Purpose of the Study:
- To investigate the nature and regulation of FRP subunit interactions using computational and site-directed mutagenesis.
- To identify key residues involved in FRP homodimer formation and stability.
Main Methods:
- In silico mutations and energetic analyses were performed to identify critical residues.
- Site-directed mutagenesis was employed to create and study the E99K variant.
- Monomer-dimer equilibrium and dissociation constants (Kd) were analyzed.
Main Results:
- Residue E99 was identified as important for FRP dimer formation, interacting with residues R113 and R225.
- E99 was found to be non-essential for FMN cofactor or substrate binding.
- The E99K variant exhibited a 44-fold increase in Kd, indicating enhanced subunit dissociation compared to the native enzyme.
Conclusions:
- Residue E99 plays a critical role in the stabilization of the Vibrio harveyi flavin reductase dimer.
- Targeting residue E99 can modulate FRP subunit interactions and dissociation, offering insights into enzyme regulation.
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