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Relaxases and Plasmid Transfer in Gram-Negative Bacteria
Ellen L Zechner1, Gabriel Moncalián2, Fernando de la Cruz2
1Institute of Molecular Biosciences, University of Graz, BioTechMed-Graz, Humboldtstrasse 50/I, 8010, Graz, Austria. ellen.zechner@uni-graz.at.
Current Topics in Microbiology and Immunology
|March 15, 2018
Summary
Relaxases are key enzymes for plasmid DNA transfer between bacteria. This review details the MOBF family
Area of Science:
- * Molecular Biology
- * Microbiology
- * Biochemistry
Background:
- * Plasmids utilize relaxases for conjugative transfer, essential for horizontal gene transfer.
- * Relaxases are crucial for both self-transmissible and mobilizable plasmids.
- * These enzymes interact with type IV secretion systems for DNA transport.
Purpose of the Study:
- * To review the MOBF family of relaxases.
- * To describe the biochemistry of these versatile enzymes.
- * To integrate current knowledge into a mechanistic model of plasmid transfer.
Main Methods:
- * Review of existing literature on MOBF relaxases.
- * Biochemical analysis of relaxase function.
- * Mechanistic modeling of plasmid transfer processes.
Main Results:
- * Relaxases bind plasmids, forming a relaxosome complex.
- * They catalyze site- and strand-specific DNA cleavage.
- * Relaxases facilitate DNA piloting through secretion channels and aid termination in recipient cells.
Conclusions:
- * Relaxases are central to the mechanism of conjugative plasmid transfer.
- * Understanding MOBF relaxases provides insight into bacterial DNA mobility.
- * A mechanistic model aids in comprehending plasmid spread in Gram-negative bacteria.
Keywords:
Bacterial conjugationBacterial type IV secretionConjugative DNA processingDNA helicasePlasmidRelaxaseMore Related Videos
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