Cloning and characterization of a gene coding for the catechol 1,2-dioxygenase of Arthrobacter sp. mA3

The catA gene, coding for the catechol 1,2-dioxygenase (C12O) of the bacterial strain Arthrobacter sp. mA3, was cloned and expressed in Escherichia coli. One plasmid containing a 6.1-kb EcoRI insert was selected by its ability to degrade catechol and to accumulate cis-cis-muconate. The DNA insert of this plasmid was mapped with restriction enzymes. The catA gene was subcloned on a 1.3-kb PstI-EcoRI fragment by deleting the adjacent restriction fragments. The nucleotide sequence of catA was determined. The C12O is coded for by a gene spanning 849 nucleotides and the deduced M(r) of the protein is 30,560. The polypeptide encoded by the cloned catA gene was expressed in an E. coli minicell system and detected by gel electrophoresis.