MICROBIAL REDUCTIVE DECHLORINATION OF TRICHLOROETHANE/CHLOROFORM AND GENOMIC CHARACTERIZATION OF THE DECHLORINATORS

Abstract

ANTHROPOGENIC HALOGENATED ORGANIC COMPOUNDS HAVE BEEN INTRODUCED TO THE ENVIRONMENT DUE TO THE WIDESPREAD USAGE AND IMPROPER DISPOSAL, WHICH POSE ADVERSE EFFECTS TO BOTH ENVIRONMENT AND HUMAN BEINGS. MICROBIAL REDUCTIVE DECHLORINATION IS AN EFFECTIVE TECHNOLOGY TO DETOXIFY CHLORINATED ORGANIC COMPOUNDS. HOWEVER, TRICHLOROETHANE, TETRACHLOROETHENE AND CHLOROFORM ARE RECALCITRANT IN THE POLLUTED SITES AND SATISFACTORY TREATMENT CANNOT BE ACHIEVED BY AVAILABLE BACTERIA. IN THIS DOCTORIAL STUDY, DESULFITOBACTERIUM SP. STRAIN PR, DEHALOCOCCOIDES MCCARTYI STRAIN 11A5 AND DEHALOBACTER-CONTAINING CO-CULTURE SN WERE FOUND TO BE ABLE TO DECHLORINATE 1,1,2-TRICHLOROETHANE, TETRACHLOROETHENE AND CHLOROFORM/1,1,1-TRICHLOROETHANE, RESPECTIVELY. MECHANISMS INVOLVED IN THESE SPECIFIC REDUCTIVE DECHLORINATION PROCESSES WERE INVESTIGATED VIA IDENTIFYING NOVEL REDUCTIVE DEHALOGENASE GENES WHICH CAN BE FURTHER USED TO DESIGN BIOMARKERS TO TARGET, PREDICT AND MONITOR REDUCTIVE DECHLORINATION OF THESE SP