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Quantification of Plasmid-Mediated Antibiotic Resistance in an Experimental Evolution Approach
Published on: December 14, 2019
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Native Plasmid-Encoded Mercury Resistance Genes Are Functional and Demonstrate Natural Transformation in
Ankita Kothari1, Drishti Soneja1, Albert Tang1
1Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, California, USA.
Msystems
|December 19, 2019
Summary
This study demonstrates that a native plasmid confers mercury resistance in bacteria. Researchers identified 17 naturally competent bacterial strains capable of acquiring this plasmid, highlighting gene transfer
Area of Science:
- Microbiology
- Environmental Science
- Genetics
Background:
- Horizontal gene transfer (HGT) via plasmids drives bacterial genetic diversity.
- The role of natural transformation in gene dissemination within groundwater environments is not well understood.
Purpose of the Study:
- To validate the function of a native plasmid-encoded mercury resistance operon.
- To investigate the prevalence and efficiency of natural transformation in groundwater bacteria.
- To understand the ecological implications of plasmid-mediated trait acquisition in dynamic environments.
Main Methods:
- Phylogenetic analysis of mercury reductases.
- Synthesis and functional validation of a native plasmid in *Escherichia coli*.
- Screening and confirmation of natural transformation in environmental bacterial isolates.
Main Results:
- A native 8-kbp plasmid conferred functional mercury resistance.
- Phylogenetic analysis revealed distinct mercury reductases in groundwater isolates.
- Seventeen naturally competent bacterial strains (Gram-positive and Gram-negative) were identified.
- Confirmed HGT via natural transformation in selected strains, conferring a growth advantage in mercury.
Conclusions:
- Native plasmids can provide advantageous traits, like mercury resistance, in groundwater.
- Natural transformation is an effective mechanism for acquiring beneficial genes in environmental bacteria.
- This process facilitates rapid adaptation to environmental stresses in microbial communities.
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