The maintenance of Plasmid-containing organisms in populations of Escherichia coli

J Gen Microbiol. 1981 Mar;123(1):129-41. doi: 10.1099/00221287-123-1-129.


Populations of Escherichia coli containing a small non-conjugative plasmid were grown in carbon-limited continuous culture. For all plasmids tested the presence of the plasmid lowered the growth rate of the host bacterium, and the proportion of plasmid-containing organisms in the total population declined initially. However, periodically, adaptive changes occurred in plasmid-containing organisms which increased their growth rate. This resulted in oscillations in the proportion of plasmid-containing organisms, and the delayed loss of the plasmid from the population.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Culture Media
  • Escherichia coli / genetics
  • Escherichia coli / growth & development*
  • Models, Biological
  • Mutation
  • Plasmids*


  • Culture Media