Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Comparative Study
. 1995 Aug;177(15):4417-26.
doi: 10.1128/jb.177.15.4417-4426.1995.

A multicopy plasmid of the extremely thermophilic archaeon Sulfolobus effects its transfer to recipients by mating

Affiliations
Comparative Study

A multicopy plasmid of the extremely thermophilic archaeon Sulfolobus effects its transfer to recipients by mating

C Schleper et al. J Bacteriol. 1995 Aug.

Abstract

A plasmid of 45 kb, designated pNOB8, was found in high copy number in a new heterotrophic Sulfolobus isolate, NOB8H2, from Japan. Dissemination of the plasmid occurred in six cultures of nine different Sulfolobus strains when small amounts of the donor were added. These mixed cultures exhibited a high average copy number of the plasmid, between 20 and 40 per chromosome, and showed a marked growth retardation. Horizontal transfer of pNOB8 was proved by isolating transcipients from mating mixtures via single colonies. In these isolates, the copy number of the plasmid appeared to be subject to a control mechanism. Cell-free filtrates of donor cultures did not transmit the plasmid, and plating of the donor on lawns of recipients did not result in plaque formation, suggesting that the transfer was not mediated by a virus. Rapid formation of cell-to-cell contacts between differently stained donor and recipient partners was demonstrated after the two strains were mixed. Electron microscopic analysis of mating mixtures revealed many cell aggregates made up of 2 to 30 cells and intercellular cytoplasmic bridges connecting two or more cells. Cells that had been transformed with purified plasmid DNA as well as transcipients isolated from mating mixtures were shown to serve as donors for further transmission of pNOB8. The plasmid undergoes extensive genetic variations, since deletions and insertions were frequently observed in plasmid preparations from the donor strain and from mating mixtures.

PubMed Disclaimer

Similar articles

Cited by

References

    1. Arch Mikrobiol. 1972;84(1):54-68 - PubMed
    1. Microbiol Rev. 1994 Jun;58(2):162-210 - PubMed
    1. Anal Biochem. 1983 Jul 1;132(1):6-13 - PubMed
    1. Microbiol Rev. 1984 Mar;48(1):24-41 - PubMed
    1. J Bacteriol. 1985 Apr;162(1):461-2 - PubMed

Publication types

LinkOut - more resources