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Iterative Optimization of DNA Duplexes for Crystallization of SeqA-DNA Complexes
Published on: November 1, 2012
DNA protection by stress-induced biocrystallization
1Department of Organic Chemistry, The Weizmann Institute of Science, Rehovot, Israel.
Nature
|July 14, 1999
Summary
Bacteria protect their DNA from environmental stress by forming intracellular crystals. This study reveals how the protein Dps co-crystallizes with DNA in Escherichia coli, sequestering and shielding it from damage.
Area of Science:
- Microbiology
- Biochemistry
- Structural Biology
Background:
- The crystalline state is generally considered incompatible with life.
- However, intracellular crystalline assemblies can protect vital macromolecules under severe environmental stress.
Purpose of the Study:
- To investigate a defense strategy in Escherichia coli involving DNA sequestration within intracellular crystals.
- To elucidate the role of the stress-induced protein Dps in this process.
Main Methods:
- Co-crystallization experiments with purified DNA and Dps protein.
- Analysis of crystalline structures formed in E. coli under stress conditions.
- Assessment of DNA protection against various assaults within crystals.
Main Results:
- Purified Dps and DNA rapidly form highly stable co-crystals, sequestering DNA.
- DNA within these crystals is effectively protected against diverse environmental assaults.
- Similar crystalline structures are observed in E. coli with overexpressed Dps and in starved wild-type bacteria.
Conclusions:
- DNA-Dps co-crystallization represents a significant DNA protection mechanism in bacteria.
- This biocrystallization strategy provides broad-spectrum DNA protection through sequestration.
- The widespread presence of Dps homologues suggests this mechanism is crucial and prevalent in prokaryotes.
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