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DNA-affinity-purified Chip DAP-chip Method to Determine Gene Targets for Bacterial Two component Regulatory Systems
Published on: July 21, 2014
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Structure, dynamics, and function of SrnR, a transcription factor for nickel-dependent gene expression
Luca Mazzei1, Francesco Musiani1, Szymon Żerko2
1Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology (FaBiT), University of Bologna, Via Giuseppe Fanin 40, I-40127 Bologna. Italy.
Metallomics : Integrated Biometal Science
|December 1, 2021
Summary
This study investigates how Streptomyces griseus regulates gene expression using a nickel-sensing system. The research reveals the structural and dynamic features of a key protein involved in this metal-dependent regulation.
Area of Science:
- Microbiology and Molecular Biology
- Biochemistry and Structural Biology
Background:
- Streptomyces griseus produces antibacterial compounds and has phytoremediation potential.
- It expresses two metal-dependent superoxide dismutase (SOD) enzymes, utilizing Fe(II) or Ni(II).
- Alternative SOD expression is controlled by a nickel-dependent two-component system (TCS).
Purpose of the Study:
- To elucidate the molecular mechanisms of the SgSrnR/SgSrnQ TCS in regulating sodF gene expression.
- To understand the structural, dynamic, and functional characteristics of the SgSrnR protein.
- To investigate how nickel (Ni(II)) influences the interaction between SgSrnR and SgSrnQ.
Main Methods:
- Integrated approaches including X-ray crystallography and Nuclear Magnetic Resonance (NMR) spectroscopy.
- Atomistic molecular dynamics simulations and isothermal titration calorimetry.
- In silico molecular docking studies.
Main Results:
- The homodimeric apo-SgSrnR protein binds to the sodF operator DNA in a two-step mechanism.
- The binding involves a rigid globular domain, leaving disordered regions accessible for interaction.
- These disordered regions are proposed to interact with the disordered SgSrnQ sensor in a Ni(II)-dependent manner.
Conclusions:
- The SgSrnR/SgSrnQ TCS regulates sodF expression through a Ni(II)-mediated interaction.
- SgSrnR's structure and dynamics are crucial for its DNA binding and interaction with SgSrnQ.
- This study provides molecular insights into metal-dependent gene regulation in Streptomyces griseus.
Keywords:
NMR spectroscopyStreptomyces griseuscalorimetrymolecular dynamicsmolecular modellingnickel homeostasis, nickel sensingprotein crystallographyMore Related Videos
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