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Updated: Jun 28, 2026
10:41
Detection of Toxin Translocation into the Host Cytosol by Surface Plasmon Resonance
Published on: January 3, 2012
Crystallization of Doc and the Phd-Doc toxin-antitoxin complex.
Abel Garcia-Pino1, Minh-Hoa Dao-Thi, Ehud Gazit
1Laboratorium voor Ultrastructuur, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium. agarciap@vub.ac.be
Summary
The PhD/Doc addiction system ensures bacteriophage P1 inheritance in E. coli. Structural studies of Doc mutants and Phd-Doc complexes reveal insights into this bacterial toxin-antitoxin system.
Area of Science:
- Molecular Biology
- Structural Biology
- Bacteriology
Background:
- The PhD/Doc system is a key addiction module for stable plasmid inheritance in bacteria.
- It serves as a model for a broader family of bacterial toxin-antitoxin systems.
Purpose of the Study:
- To elucidate the structural basis of the PhD/Doc addiction system.
- To characterize the crystal structures of Doc mutants and Phd-Doc complexes.
Main Methods:
- X-ray crystallography was employed to determine the structures.
- Crystallization of Doc(H66Y) mutant, Doc(H66Y)/Phd(52-73Se) complex, and wild-type Phd-Doc complex were performed.
- Diffraction data were collected using synchrotron radiation.
Main Results:
- The His66Tyr mutant of Doc (Doc(H66Y)) was crystallized and diffracted to 2.5 A resolution.
- A complex of Doc(H66Y) with a Phd peptide diffracted to 1.9 A resolution.
- Crystals of the wild-type Phd-Doc complex diffracted to 2.4 A resolution.
Conclusions:
- The study provides structural data for the PhD/Doc system.
- These findings contribute to understanding bacteriophage P1 inheritance and bacterial toxin-antitoxin mechanisms.
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