ANALYSIS OF TRICHLOROETHENE DEGRADATION BY PHENOL HYDROXYLASE USING FLUORESCENT PROTEIN AS A REPORTER

Abstract

 Trichloroethene (TCE) is a major groundwater contaminant in many developed countries. TCE is known to be degraded by phenol hydroxylase (PH) aerobically. Although many phenol-utilizing bacteria have been isolated, each bacterium has its own TCE degradability. Reasons on the difference in TCE degradability among isolates are not clear in many cases. Here, we have developed a method able to evaluate TCE degradability of PH gene itself by using a common host and the tac promoter for constitutive expression. A green fluorescent protein gene was also used as a reporter. These genes were integrated into chromosome of a host strain by using a Tn5 transposon vector. Transconjugants having each PH gene were isolated, and TCE degradability were compared each other. Results showed that TCE degradability was different among 6 PH genes. The fluorescence analysis showed that transcription level and the degradation efficiency were significantly different among them.