R factor

plasmid class

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Last updated

June 17, 2026

Quick Summary

An R factor is a type of plasmid found in bacteria that provides resistance to antibiotics. Plasmids are small, circular DNA molecules that exist outside the main bacterial chromosome and can replicate independently. While not essential for a bacterium's survival, plasmids can offer advantages, such as antibiotic resistance conferred by R factors.12

Some R factors can transfer themselves between bacterial cells, allowing antibiotic resistance to spread rapidly through a population. This ability makes R factors significant in the study of antibiotic resistance and has implications for bacterial infections.2

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plasmid
Another class of plasmids, R factors, confers upon bacteria resistance to antibiotics. Some Col factors and R factors can transfer themselves from one cell to another and thus are capable of spreading rapidly through a bacterial population. A plasmid that is attached to the cell membrane or integrated into…
Read More
Another class of plasmids, R factors, confers upon bacteria resistance to antibiotics. Some Col factors and R factors can transfer themselves from one cell to another and thus are capable of spreading rapidly through a bacterial population. A plasmid that is attached to the cell membrane or integrated into…
Read More