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 Nemergut, D. R.
Right arrow Articles by Schmidt, S. K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Nemergut, D. R.
Right arrow Articles by Schmidt, S. K.
Agricola
Right arrow Articles by Nemergut, D. R.
Right arrow Articles by Schmidt, S. K.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, February 2004, p. 1160-1168, Vol. 70, No. 2
0099-2240/04/$08.00+0     DOI: 10.1128/AEM.70.2.1160-1168.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.

Integron Diversity in Heavy-Metal-Contaminated Mine Tailings and Inferences about Integron Evolution

D. R. Nemergut, A. P. Martin, and S. K. Schmidt*

Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado 80309

Received 2 September 2003/ Accepted 28 October 2003

Integrons are horizontal gene transfer (HGT) systems containing elements necessary for site-specific recombination and expression of foreign DNA. The overall phylogenetic distribution of integrons and range of genes that can be transferred by integrons are unknown. This report contains an exploration of integrons in an environmental microbial community and an investigation of integron evolution. First, using culture-independent techniques, we explored the diversity of integrons and integron-transferred genes in heavy-metal-contaminated mine tailings. Using degenerate primers, we amplified integron integrase genes from the tailings. We discovered 14 previously undescribed integrase genes, including six novel gene lineages. In addition, we found 11 novel gene cassettes in this sample. One of the gene cassettes that we sequenced is similar to a gene that codes for a step in a pathway for nitroaromatic catabolism, a group of compounds associated with mining activity. This suggests that integrons may be important for gene transfer in response to selective pressures other than the presence of antibiotics. We also investigated the evolution of integrons by statistically comparing the phylogenies of 16S rRNA and integrase genes from the same organisms, using sequences from GenBank and various sequencing projects. We found significant differences between the organismal (16S rRNA) and integrase trees, and we suggest that these differences may be due to HGT.

* Corresponding author. Mailing address: Campus Box 334, Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309. Phone: (303) 492-6248. Fax: (303) 492-8699. E-mail: schmidts{at}spot.colorado.edu.

Applied and Environmental Microbiology, February 2004, p. 1160-1168, Vol. 70, No. 2
0099-2240/04/$08.00+0     DOI: 10.1128/AEM.70.2.1160-1168.2004
Copyright © 2004, 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 © 2004 by the American Society for Microbiology. All rights reserved.