EVALUATION OF TRICHLOROETHYLENE AND PHENOLDECOMPOSING CAPACITY OF MICROBE, AND PREPARATION OF VARIANT PHENOL HYDROXYLASE

摘要

PROBLEM TO BE SOLVED: To provide a method for specifying a DNA region influencing the activity of phenol hydroxylase and efficiently removing TCE from a polluted environment. SOLUTION: This method is for evaluating TCE and phenol-decomposing capacity of microbes capable of producing phenol hydroxylase, based on the affinity, for TCE and phenol, of an amino acid located at the X in Asp-Glu-X- Arg-His, the amino acid sequence contained in the α subunit of phenol hydroxylase. A variant phenol hydroxylase gene is prepared by modifying a base sequence of the gene encoding the α subunit so that the amino acid which is located at the X in Asp-Glu-X-His as the amino acid sequence contained in the αsubunit of phenol hydroxylase encodes an amino acid having high affinity for TCE. By this method, microbial strains having high TCE or phenol- decomposing capacity can be rapidly selected and microbial strains having high TCE-decomposing capacity can be prepared.