Previous Article | Next Article ![]()
Appl. Environ. Microbiol., Jul 1996, 2317-2323, Vol 62, No. 7
C Kuo and BRS Genthner
The effect of added Cd(II), Cu(II), Cr(VI), or Hg(II) at 0.01 to 100 ppm on
metabolism in anaerobic bacterial consortia which degrade 2-chlorophenol
(2CP), 3-chlorobenzoate (3CB), phenol, and benzoate was examined. Three
effects were observed, including extended acclimation periods (0.1 to 2.0
ppm), reduced dechlorination or biodegradation rates (0.1 to 2.0 ppm), and
failure to dechlorinate or biodegrade the target compound (0.5 to 5.0 ppm).
3CB biodegradation was most sensitive to Cd(II) and Cr(VI). Biodegradation
of benzoate and phenol was most sensitive to Cu(II) and Hg(II),
respectively. Adding Cr(VI) at 0.01 ppm increased biodegradation rates of
phenol (177%) and benzoate (169%), while Cd(II) and Cu(II) at 0.01 ppm
enhanced biodegradation rates of benzoate (185%) and 2CP (168%),
respectively. Interestingly, with Hg(II) at 1.0 to 2.0 ppm, 2CP and 3CB
were biodegraded 133 to 154% faster than controls after an extended
acclimation period, suggesting adaptation to Hg(II). Metal ions were added
at inhibitory, but sublethal, concentrations to investigate effects on
metabolic intermediates and end products. Phenol accumulated to
concentrations higher than those in controls only in the 2CP consortium
with added Cu(II) at 1.2 ppm but was subsequently degraded. There was no
effect on benzoate, and little effect on acetate intermediates was
observed. In most cases, methane yields were reduced by 23 to 97%. Thus,
dehalogenation, aromatic degradation, and methanogenesis in these anaerobic
consortia showed differential sensitivities to the heavy metal ions added.
These data indicate that the presence of heavy metals can affect the
outcome of anaerobic bioremediation of aromatic pollutants. In addition, a
potential exists to use combinations of anaerobic bacterial species to
bioremediate sites contaminated with both heavy metals and aromatic
pollutants.
Copyright © 1996, American Society for Microbiology
Effect of Added Heavy Metal Ions on Biotransformation and Biodegradation of 2-Chlorophenol and 3-Chlorobenzoate in Anaerobic Bacterial Consortia
Department of Biology and Center for Environmental Diagnostics and Bioremediation, University of West Florida, Pensacola, Florida 32514
This article has been cited by other articles:
| J. Bacteriol. | Microbiol. Mol. Biol. Rev. | Eukaryot. Cell | All ASM Journals |
|---|