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Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols
Published on: April 4, 2014
Opposite allosteric mechanisms in TetR and CAP.
Jennifer E Seedorff1, Michael E Rodgers, Robert Schleif
1Department of Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, USA.
Protein Science : a Publication of the Protein Society
|March 25, 2009
Summary
Oligomeric protein DNA binding affinity is regulated intrinsically or extrinsically. TetR repressor uses an extrinsic mechanism, altering domain positions, while catabolite activator protein (CAP) uses an intrinsic mechanism, modulating individual domain affinity.
Area of Science:
- Molecular Biology
- Biochemistry
- Genetics
Background:
- Oligomeric proteins regulate DNA binding through intrinsic or extrinsic mechanisms.
- Intrinsic regulation involves modulating individual DNA-binding domain affinity.
- Extrinsic regulation alters the relative positions of DNA-binding domains.
Purpose of the Study:
- To elucidate the specific regulatory mechanisms employed by TetR repressor and CAP.
- To differentiate between intrinsic and extrinsic DNA binding regulation in these proteins.
Main Methods:
- Direct experimental demonstration of regulatory mechanisms.
- Analysis of protein-DNA interactions and domain positioning.
- Investigating effector molecule influence on protein conformation.
Main Results:
- TetR repressor was shown to utilize an extrinsic regulatory mechanism.
- Catabolite activator protein (CAP) was demonstrated to employ an intrinsic regulatory mechanism.
- Distinct molecular strategies for DNA binding affinity control were identified.
Conclusions:
- TetR repressor regulates DNA binding by altering the spatial arrangement of its domains.
- CAP regulates DNA binding by modulating the affinity of its individual DNA-binding domains.
- These findings highlight diverse strategies for controlling gene expression through protein-DNA interactions.
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