It is important to prevent accumulation of toxic intermediates in dechlorination and detoxification of chlorinated ethylenes by bacteria. We attempted dechlorination of accumulated vinylchloride, an intermediate product of chlorinated ethylene dechlorination, in enriched culture. Dechlorination of vinyl chloride only occurred when it was coupled with cis-dichloroethylene dechlorination, and it was the cause of vinyl chloride accumulation. Intermittent addition of hydrogen showed no effect on dechlorination, except when the dechlorination competed with sulfate reduction. When sulfate was abundant in the culture, vinylchloride dechlorination did not occur even in the presence of cis-dichloroethylene. Hydrogen depletion may hinder vinylchloride dechlorination under such condition.

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 Phenol-utilizing bacterium, Cupriavidus sp. TW2, is able to degrade Trichloroethene (TCE) by phenol hydroxylase (PH) induced by phenol. Homologous recombination was carried out to insert the tac promoter (P_tac) upstream of PH genes for constitutive expression. The resultant strain, TW2-P, showed the higher TCE degradability without the phenol induction. As a next step, a gene encoding the green fluorescent protein (GPF) was inserted downstream of PH genes by the homologous recombination for single cell monitoring. We succeeded in constructing the strain TW2-PGF that can be monitored as a single cell with a fluorescence microscope. The insertion of GFP gene did not affect the TCE degradability of TW2-P.

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 There were the following typos in the article, "Journal of Japan Society of Civil Engineers, Ser. G (Environmental Research) Vol. 69 (2013) , No. 4 pp. 183-195"

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