TY - JOUR
T1 - Characterization of phenol and trichloroethene degradation by the rhizobium Ralstonia taiwanensis
AU - Chen, Wen Ming
AU - Chang, Jo Shu
AU - Wu, Chih Hui
AU - Chang, Shu Chen
N1 - Funding Information:
This work was supported by grants from the National Science Council, Taiwan, Republic of China (NSC 92-2313-B-022-001 and 92-2313-B-022-001-008).
PY - 2004/10
Y1 - 2004/10
N2 - Ralstonia taiwanensis is a root nodule bacterium originally isolated from Mimosa sp. in southern Taiwan. Some strains of R. taiwanensis demonstrated the ability to grow on medium containing phenol as the sole carbon source, especially strain TJ86, which was able to survive and grow at phenol concentrations of up to 900 mg/l. The dependence of the phenol degradation rate on the phenol concentration can be described by Haldane's model with a low KS (the apparent half-saturation constant) of 5.46 μM and an extremely high KSI (the apparent inhibition constant) 9075 μM. The optimal phenol degradation rate was 61 μmol/min/g cell, which occurred at a phenol concentration of 228 μM. The phenol-limited growth kinetics of TJ86 by Andrews's model also followed a similar trend to that of phenol degradation, indicating the close links between phenol degradation and cell growth. Strain TJ86 also achieved 100 and 40% degradation for soil samples amended with 500 and 1000 μg phenol/g soil (dry weight) within 9 days, respectively. Moreover, strain TJ86 cometabolically degraded trichloroethene (TCE) after being cultivated with media containing phenol or m-cresol as the carbon substrate. The sequence of the large-subunit phenol hydroxylase (LmPH) gene obtained from TJ86 displayed high homology to that of other phenol-utilizing bacteria. Results from kinetic and phylogenetic analyses suggest that strain TJ86 most likely belongs to group I phenol-degrading bacteria which are considered to be efficient TCE degraders. It is proposed that the symbiotic relationship between rhizobia R. taiwanensis and its host plant Mimosa sp. may have the potential for rhizoremediation of aquatic and soil environments contaminated by phenol and TCE.
AB - Ralstonia taiwanensis is a root nodule bacterium originally isolated from Mimosa sp. in southern Taiwan. Some strains of R. taiwanensis demonstrated the ability to grow on medium containing phenol as the sole carbon source, especially strain TJ86, which was able to survive and grow at phenol concentrations of up to 900 mg/l. The dependence of the phenol degradation rate on the phenol concentration can be described by Haldane's model with a low KS (the apparent half-saturation constant) of 5.46 μM and an extremely high KSI (the apparent inhibition constant) 9075 μM. The optimal phenol degradation rate was 61 μmol/min/g cell, which occurred at a phenol concentration of 228 μM. The phenol-limited growth kinetics of TJ86 by Andrews's model also followed a similar trend to that of phenol degradation, indicating the close links between phenol degradation and cell growth. Strain TJ86 also achieved 100 and 40% degradation for soil samples amended with 500 and 1000 μg phenol/g soil (dry weight) within 9 days, respectively. Moreover, strain TJ86 cometabolically degraded trichloroethene (TCE) after being cultivated with media containing phenol or m-cresol as the carbon substrate. The sequence of the large-subunit phenol hydroxylase (LmPH) gene obtained from TJ86 displayed high homology to that of other phenol-utilizing bacteria. Results from kinetic and phylogenetic analyses suggest that strain TJ86 most likely belongs to group I phenol-degrading bacteria which are considered to be efficient TCE degraders. It is proposed that the symbiotic relationship between rhizobia R. taiwanensis and its host plant Mimosa sp. may have the potential for rhizoremediation of aquatic and soil environments contaminated by phenol and TCE.
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U2 - 10.1016/j.resmic.2004.05.004
DO - 10.1016/j.resmic.2004.05.004
M3 - Article
C2 - 15380556
AN - SCOPUS:4544268017
SN - 0923-2508
VL - 155
SP - 672
EP - 680
JO - Research in Microbiology
JF - Research in Microbiology
IS - 8
ER -