- Plasmids occur naturally in a variety of hosts, primarily bacteria but also archaea and eukaryotes.
- In bacteria, plasmids are often studied in Escherichia coli for genetic engineering and molecular biology.
- Other bacterial hosts include Bacillus subtilis, Pseudomonas aeruginosa, and Staphylococcus aureus, which carry plasmids linked to processes like sporulation, multidrug resistance, and antibiotic resistance.
- The Ti plasmid in Agrobacterium tumefaciens is notable for its role in plant genetic modifications.
- In archaea, species like Haloferax volcanii and Sulfolobus spp. host plasmids adapted to extreme environments, such as high salinity or temperatures.
- Among eukaryotes, yeasts like Saccharomyces cerevisiae contain 2µ plasmids, widely utilized in research and biotechnology.
- These natural hosts provide insights into plasmid biology, ecological roles, and their evolutionary adaptations.
