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Whole-cell kinetics of trichloroethylene degradation by phenol hydroxylase in a ralstonia eutropha JMP134 derivative

ABSTRACT: The rate, progress, and limits of trichloroethylene (TCE) degradation by Ralstonia eutropha AEK301/pYK3021 whole cells were examined in the absence of aromatic induction. At TCE concentrations up to 800 &mgr;M, degradation rates were sustained until TCE was no longer detectable. The Ks and Vmax for TCE degradation by AEK301/pYK3021 whole cells were determined to be 630 &mgr;M and 22.6 nmol/min/mg of total protein, respectively. The sustained linear rates of TCE degradation by AEK301/pYK3021 up to a concentration of 800 &mgr;M TCE suggest that solvent effects are limited during the degradation of TCE and that this construct is little affected by the formation of toxic intermediates at the TCE levels and assay duration tested. TCE degradation by this strain is subject to carbon catabolite repression.

SUBMITTER: Ayoubi PJ

PROVIDER: S-EPMC106651 | biostudies-literature | 1998 Nov

REPOSITORIES: biostudies-literature

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Whole-cell kinetics of trichloroethylene degradation by phenol hydroxylase in a ralstonia eutropha JMP134 derivative

Ayoubi PJ Harker AR

Applied and environmental microbiology 19981101 11

The rate, progress, and limits of trichloroethylene (TCE) degradation by Ralstonia eutropha AEK301/pYK3021 whole cells were examined in the absence of aromatic induction. At TCE concentrations up to 800 &mgr;M, degradation rates were sustained until TCE was no longer detectable. The Ks and Vmax for TCE degradation by AEK301/pYK3021 whole cells were determined to be 630 &mgr;M and 22.6 nmol/min/mg of total protein, respectively. The sustained linear rates of TCE degradation by AEK301/pYK3021 up t ...[more]

PMID: 9797289

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