Abstract
Sphingomonas paucimobilis UT26 uses γ-hexachlorocyclohexane (γ-HCH) as a sole source of carbon and energy. In UT26, γ-HCH is converted to 2, 5-dichlorohydroquinone (2, 5-DCHQ). To clone a gene that is involved in the degradation of 2, 5-DCHQ, a Tn5 mutation was introduced into UT26, and three mutants (UT102, UT103, and UT116) defective in 2, 5-DCHQ degradation were visually selected by spraying γ-HCH solution on the colonies. 2, 5-DCHQ and hydroquinone (HQ) degradation activities of these three mutants and UT26 were analyzed using resting cells. The three mutants had different phenotypes. It was also demonstrated that 2, 5-DCHQ and HQ degradation activities were inducibly expressed in UT26 in the presence of 2, 5-DCHQ.
