| Autor: |
Xie Y; Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States.; Center for Environmental Biotechnology, University of Tennessee, Knoxville, Tennessee 37996, United States.; Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States., Chen G; Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States.; Center for Environmental Biotechnology, University of Tennessee, Knoxville, Tennessee 37996, United States., May AL; Center for Environmental Biotechnology, University of Tennessee, Knoxville, Tennessee 37996, United States., Yan J; Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning 110016, China., Brown LP; Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States., Powers JB; Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States., Campagna SR; Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States.; Biological and Small Molecule Mass Spectrometry Core, University of Tennessee, Knoxville, Tennessee 37996, United States., Löffler FE; Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States.; Center for Environmental Biotechnology, University of Tennessee, Knoxville, Tennessee 37996, United States.; Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States.; Department of Microbiology, University of Tennessee, Knoxville, Tennessee 37996, United States.; Department of Biosystems Engineering and Soil Science, University of Tennessee, Knoxville, Tennessee 37996, United States. |
| Abstrakt: |
Fluorinated organic compounds have emerged as environmental constituents of concern. We demonstrate that the alkane degrader Pseudomonas sp. strain 273 utilizes terminally monofluorinated C 7 -C 10 alkanes and 1,10-difluorodecane (DFD) as the sole carbon and energy sources in the presence of oxygen. Strain 273 degraded 1-fluorodecane (FD) (5.97 ± 0.22 mM, nominal) and DFD (5.62 ± 0.13 mM, nominal) within 7 days of incubation, and 92.7 ± 3.8 and 90.1 ± 1.9% of the theoretical maximum amounts of fluorine were recovered as inorganic fluoride, respectively. With n -decane, strain 273 attained (3.24 ± 0.14) × 10 7 cells per μmol of carbon consumed, while lower biomass yields of (2.48 ± 0.15) × 10 7 and (1.62 ± 0.23) × 10 7 cells were measured with FD or DFD as electron donors, respectively. The organism coupled decanol and decanoate oxidation to denitrification, but the utilization of (fluoro)alkanes was strictly oxygen-dependent, presumably because the initial attack on the terminal carbon requires oxygen. Fluorohexanoate was detected as an intermediate in cultures grown with FD or DFD, suggesting that the initial attack on the fluoroalkanes can occur on the terminal methyl or fluoromethyl groups. The findings indicate that specialized bacteria such as Pseudomonas sp. strain 273 can break carbon-fluorine bonds most likely with oxygenolytic enzyme systems and that terminally monofluorinated alkanes are susceptible to microbial degradation. The findings have implications for the fate of components associated with aqueous film-forming foam (AFFF) mixtures. |
