Microbial linear plasmids (original) (raw)

Abstract

While plasmids were originally considered to be generally circular until almost two decades ago, linear elements were reported to exist as well. They are now known to be common genetic elements in both, pro- and eukaryotes. Two types of linear plasmids exist, the so-called hairpin plasmids with covalently closed ends and those with proteins bound to their 5′ termini. Hairpin plasmids are common in human-pathogenic Borrelia spirochetes, in which they are instrumental in escape from the immunological response; cryptic hairpin elements are present in mitochondria of the plant pathogenic fungus Rhizoctonia solani. Plasmids with 5′ attached proteins constitute the largest group. In actinomycetous bacteria they are conjugative and usually confer advantageous phenotypes, e.g. formation of antibiotics, degradation of xenobiotics, heavy-metal resistance and growth on hydrogen as the sole energy source. In contrast, the majority of linear plasmids from eukaryotes are cryptic, with only a few exceptions. In some yeasts a killer phenotype may be associated, the most thoroughly investigated elements being those from Kluyveromyces lactis killer strains. In Neurospora spp. and in Podospora anserina, senescence and longevity respectively are correlated with linear plasmids. This review focuses on the biology of linear plasmids, their environmental significance and their use as tools in molecular and applied microbiology.

Access this article

Log in via an institution

Subscribe and save

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

Author information

Authors and Affiliations

  1. Institut für Mikrobiologie, Westfälische Wilhelms-Universität, Corrensstr. 3, D-48149 Münster, Germany Fax: +49 251 8338388, , , , , , DE
    F. Meinhardt & M. Larsen
  2. Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA, , , , , , US
    R. Schaffrath

Authors

  1. F. Meinhardt
    You can also search for this author inPubMed Google Scholar
  2. R. Schaffrath
    You can also search for this author inPubMed Google Scholar
  3. M. Larsen
    You can also search for this author inPubMed Google Scholar

Additional information

Received: 15 November 1996 / Received revision: 23 December 1996 / Accepted: 30 December 1996

Rights and permissions

About this article

Cite this article

Meinhardt, F., Schaffrath, R. & Larsen, M. Microbial linear plasmids.Appl Microbiol Biotechnol 47, 329–336 (1997). https://doi.org/10.1007/s002530050936

Download citation

Keywords