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Quantification of Plasmid-Mediated Antibiotic Resistance in an Experimental Evolution Approach
Published on: December 14, 2019
Distribution and diversity of mycoplasma plasmids: lessons from cryptic genetic elements
Marc Breton1, Florence Tardy, Emilie Dordet-Frisoni
1University Bordeaux, UMR 1332 Biologie du Fruit et Pathologie, 71 avenue Edouard Bourlaux, F-33140, Villenave d'Ornon, France.
BMC Microbiology
|November 14, 2012
Summary
Mycoplasma plasmids, previously poorly understood, are abundant in some species and likely transfer between them. A unique plasmid, pMyBK1, shows potential as a gene vector for Mycoplasma mycoides cluster species.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Mycoplasma evolution involves genome reduction and horizontal gene transfer.
- Mobile genetic elements in mycoplasmas are poorly characterized, especially plasmids.
- Limited knowledge exists on mycoplasma plasmids, hindering understanding of gene transfer mechanisms.
Purpose of the Study:
- To characterize plasmids in ruminant mycoplasmas.
- To investigate the diversity and genetic organization of mycoplasma plasmids.
- To explore the potential of mycoplasma plasmids as gene vectors.
Main Methods:
- Isolation and complete sequencing of 21 plasmids from ruminant mycoplasmas.
- Comparative analysis of sequenced plasmids with previously reported ones.
- Phylogenetic analysis to determine plasmid relationships.
- Functional analysis of pMyBK1 for replication in different Mycoplasma species.
Main Results:
- Several ruminant mycoplasma species harbor rolling-circle replicating plasmids, primarily within the Mycoplasma mycoides cluster.
- Plasmids exhibit mosaic structures, similar sizes, and genetic organization, except for the unique, larger, and mobilizable plasmid pMyBK1.
- Phylogenetic analysis distinguishes pMyBK1 from other mycoplasma plasmids and related replicons in phytoplasmas and Firmicutes.
- pMyBK1 derivatives successfully replicated in various M. mycoides cluster species, indicating potential as gene vectors.
Conclusions:
- Mycoplasma plasmids present a novel picture, being abundant in certain species.
- These plasmids likely contribute to gene exchange between mycoplasmas sharing hosts or niches.
- The unique plasmid pMyBK1 offers significant potential for developing gene vectors within the Mycoplasma mycoides cluster.
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