Journal
FEMS MICROBIOLOGY ECOLOGY
Volume 51, Issue 1, Pages 99-107Publisher
OXFORD UNIV PRESS
DOI: 10.1016/j.femsec.2004.07.011
Keywords
nahAc; C-14-naphthalene mineralization; petroleum hydrocarbon; degradation potential; oxic; subsurface
Categories
Ask authors/readers for more resources
In this study, we evaluated whether the abundance of the functional gene nahAc reflects aerobic naphthalene degradation potential in subsurface and surface samples taken from three petroleum hydrocarbon contaminated sites in southern Finland. The type of the contamination at the sites varied from lightweight diesel oil to high molecular weight residuals of crude oil. Samples were collected from both oxic and anoxic soil layers. The naphthalene dioxygenase gene nahAc was quantified using a replicate limiting dilution-polymerase chain reaction (RLD-PCR) method with a degenerate primer pair. In the non-contaminated samples nahAc genes were not detected. In the petroleum hydrocarbon-contaminated oxic soil samples nahAc gene abundance [range 3 x 10(1)-9 x 10(2) copies (g dry wt soil)(-1)] was correlated (Kendall non-parametric correlation r(2) = 0.459, p < 0.01) with the aerobic C-14-naphthalene mineralization potential (range 1 x 10(-5)-0.1 d(-1)) measured in microcosms at in situ temperatures (8 degreesC for subsurface and 20 degreesC for surface soil samples). In these samples nahAc gene abundance was also correlated with total microbial cell counts (r(2) = 0.471, p < 0.01), respiration rate (r(2) = 0.401, p < 0.01) and organic matter content (r(2) = 0.341, p <0.05). NahAc genes were amplified from anoxic soil layers indicating that, although involved in aerobic biodegradation of naphthalene, these genes or related sequences were also present in the anoxic subsurface. In the samples taken from the anoxic layers, the aerobic C-14-naphthalene mineralization rates were not correlated with nahAc gene abundance. In conclusion, current sequence information provides the basis for a robust tool to estimate the naphthalene degradation potential at oxic zones of different petroleum hydrocarbon-contaminated sites undergoing in situ bioremediation. (C) 2004 Federation of European Microbiological Societies. Published by Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available