Mechanisms and enhancement of plant metabolism of chlorinated hydrocarbons

The biotransformation of CCl₄ by pure cultures of poplar cells was investigated to understand the mechanism of the degradation of fully chlorinated hydrocarbons by poplar trees. CCl₄ metabolism was inhibited by CO and isonizid. Chloroform was produced during the transformation of CCl₄ along with CO₂. These results support the hypothesis that an enzyme similar to mammaliam cytochrome P450 2E1 is responsible for the degradation of chlorinated hydrocarbons in plants. The genes for mammalian cytochrome P450 2E1 were introduced into tobacco and poplar plants. Transformed tobacco exposed to trichloroethylene (TCE) produced 10-37 times the amount of trichloroethanol, a TCE metabolite, compared with control plants. Transformed poplar plants also produced larger amounts of trichloroethanol but to a lesser degree than tobacco.