Pseudomonas sp. DJ-12 degrades r-chlorobenzoate through hydrolytic dechlorination to produce 4-hydroxybenzoate and a chloride ion.
The fcbB gene encoding the 4-chlorbenzoate-coenzyme A (4CBA-CoA) dehalogenase which catalyzes the nucleophilic substitution reaction to convert 4CBA-CoA to 4-hydroxybenzoate-coenzyme A (4HBA-CoA) in the consecutive steps of dechlorination was cloned from the chromosome of the organism.
A nucleotide sequence analysis of the gene showed an open reading frame consisting of 810 nucleotides, which can encode for a polypeptide of molecular mass 30 kDa, containing 269 amino acid residues.
A promoter-like sequence (-35 and -10 region) and a putative ribosome-binding sequence were identified.
A deduced amino acid sequence of the 4CBA-CoA dehalogenase showed 86%, 50%, and 50% identity with those of corresponding enzymes in the Pseudomonas sp.
CBS3, Arthrobacter sp.SU, and Arthrobacter sp. TM1, respectively.
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