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Updated: Jul 7, 2026
06:48
CD Spectroscopy to Study DNA-Protein Interactions
Published on: February 10, 2022
TraR auto-inducer enhances protein backbone fluctuations in DNA binding domain
Jocelyne Vreede1, Klaas J Hellingwerf, Wim Crielaard
1Department of Molecular Microbial Physiology, Swammerdam Institute for Life Sciences, Faculty of Science, Universiteit van Amsterdam, Nieuwe Achtergracht 166, Amsterdam, The Netherlands. vreede@science.uva.nl
FEBS Letters
|February 16, 2008
Summary
Agrobacterium tumefaciens uses N-3-oxo-octanoyl-l-homoserine lactone (OOHL) to regulate gene expression via the TraR protein. Molecular dynamics simulations reveal OOHL binding enhances protein fluctuations, potentially aiding DNA binding.
Area of Science:
- Microbiology
- Molecular Biology
- Biophysics
Background:
- Agrobacterium tumefaciens employs quorum sensing for gene regulation.
- The TraR protein, a signaling transcription factor, mediates this process.
- TraR comprises a PAS-domain for OOHL binding and an HTF-motif for DNA interaction.
Purpose of the Study:
- To investigate the influence of OOHL on TraR protein dynamics using molecular dynamics.
- To understand the molecular mechanisms by which OOHL affects TraR function.
Main Methods:
- Molecular Dynamics (MD) simulations were employed.
- Analysis focused on OOHL-protein interactions and domain fluctuations.
Main Results:
- OOHL binding pocket interactions with water induce dynamic changes.
- OOHL binding increases fluctuations in the PAS-domain.
- Importantly, OOHL binding also enhances fluctuations in the DNA-binding HTF-motif.
Conclusions:
- OOHL binding to TraR induces protein-wide fluctuations.
- These dynamics may be crucial for facilitating TraR's DNA binding and transcriptional regulation.
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