A genetic structure in a cell that can replicate independently of the chromosomes, typically a small circular DNA strand in the cytoplasm of a bacterium or protozoan. Plasmids are much used in the laboratory manipulation of genes. Compare with episome.
More example sentences
- The bacterium contains a plasmid, a circular piece of DNA that holds the gene and promoter sequence.
- The replication control genes of bacterial plasmids face selection at two conflicting levels.
- We note, however, that few if any of the genes borne by bacterial plasmids are under strong positive selection at all times.
Definition of plasmid in:
- The British & World English dictionary