AEM
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Mercer, D. K.
Right arrow Articles by Flint, H. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Mercer, D. K.
Right arrow Articles by Flint, H. J.
Agricola
Right arrow Articles by Mercer, D. K.
Right arrow Articles by Flint, H. J.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, January 1999, p. 6-10, Vol. 65, No. 1
0099-2240/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.

Fate of Free DNA and Transformation of the Oral Bacterium Streptococcus gordonii DL1 by Plasmid DNA in Human Saliva

Derry K. Mercer,1,* Karen P. Scott,1 Wendy A. Bruce-Johnson,1 L. Anne Glover,2 and Harry J. Flint1

Rowett Research Institute, Bucksburn,1 and Department of Molecular and Cell Biology, University of Aberdeen, IMS, Foresterhill,2 Aberdeen, Great Britain

Received 6 July 1998/Accepted 14 October 1998

Competitive PCR was used to monitor the survival of a 520-bp DNA target sequence from a recombinant plasmid, pVACMC1, after admixture of the plasmid with freshly sampled human saliva. The fraction of the target remaining amplifiable ranged from 40 to 65% after 10 min of exposure to saliva samples from five subjects and from 6 to 25% after 60 min of exposure. pVACMC1 plasmid DNA that had been exposed to degradation by fresh saliva was capable of transforming naturally competent Streptococcus gordonii DL1 to erythromycin resistance, although transforming activity decreased rapidly, with a half-life of approximately 50 s. S. gordonii DL1 transformants were obtained in the presence of filter-sterilized saliva and a 1-µg/ml final concentration of pVACMC1 DNA. Addition of filter-sterilized saliva instead of heat-inactivated horse serum to S. gordonii DL1 cells induced competence, although with slightly lower efficiency. These findings indicate that DNA released from bacteria or food sources within the mouth has the potential to transform naturally competent oral bacteria. However, further investigations are needed to establish whether transformation of oral bacteria can occur at significant frequencies in vivo.

* Corresponding author. Mailing address: Rowett Research Institute, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, Great Britain. Phone: 44 (0) 1224 712751. Fax: 44 (0) 1224 716687. E-mail: d.mercer{at}rri.sari.ac.uk.

Applied and Environmental Microbiology, January 1999, p. 6-10, Vol. 65, No. 1
0099-2240/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. Microbiol. Mol. Biol. Rev. Eukaryot. Cell All ASM Journals

Copyright © 1999 by the American Society for Microbiology. All rights reserved.