Several streptomycetes known to metabolize organochlorides or lignocellulose were tested for their ability to break the recalcitrant carbon-chlorine bond using the insecticide lindane (hexachlorocyclohexane) as a model substrate. Streptomyces PSI rapidly converted [U-14C] lindane to a mixture of water-soluble metabolites when grown on tryptone-yeast extract at 28°C for one to five days. Chemical analysis of the products showed extensive aromatization with formation of a trichlorophenol, as well as extensive conversion to water-soluble acids, other more hydrophilic products, and CO2. Several pigment-negative mutants were isolated which still converted lindane to the same metabolites, but the wild-type organism would not grow on lindane as its sole carbon source. With higher concentrations of lindane (0.1 mg/ml), both the wild-type and a pig-mutant strain converted 20% to water solubility in six days.
