Functionality of the TOL plasmid under varying environmental conditions following conjugal transfer.
Journal Article (Journal Article)
Conjugation of catabolic plasmids in contaminated environments is a naturally occurring horizontal gene transfer phenomenon, which could be utilized in genetic bioaugmentation. The potentially important parameters for genetic bioaugmentation include gene regulation of transferred catabolic plasmids that may be controlled by the genetic characteristics of transconjugants as well as environmental conditions that may alter the expression of the contaminant-degrading phenotype. This study showed that both genomic guanine-cytosine contents and phylogenetic characteristics of transconjugants were important in controlling the phenotype functionality of the TOL plasmid. These genetic characteristics had no apparent impact on the stability of the TOL plasmid, which was observed to be highly variable among strains. Within the environmental conditions tested, the addition of glucose resulted in the largest enhancement of the activities of enzymes encoded by the TOL plasmid in all transconjugant strains. Glucose (1 g/L) enhanced the phenotype functionality by up to 16.4 (±2.22), 30.8 (±7.03), and 90.8 (±4.56)-fold in toluene degradation rates, catechol 2,3-dioxygenase enzymatic activities, and xylE gene expression, respectively. These results suggest that genetic limitations of the expression of horizontally acquired genes may be overcome by the presence of alternate carbon substrates. Such observations may be utilized in improving the effectiveness of genetic bioaugmentation.
Full Text
Duke Authors
Cited Authors
- Ikuma, K; Gunsch, CK
Published Date
- January 2013
Published In
Volume / Issue
- 97 / 1
Start / End Page
- 395 - 408
PubMed ID
- 22367613
Electronic International Standard Serial Number (EISSN)
- 1432-0614
International Standard Serial Number (ISSN)
- 0175-7598
Digital Object Identifier (DOI)
- 10.1007/s00253-012-3949-8
Language
- eng