STRUCTURE OF CATECHOL 2,3-DIOXYGENASE GENE ENCODED IN CHROMOSOMAL DNAOF PSEUDOMONAS-PUTIDA KF715

A catechol 2,3-dioxygenase gene in chromosomal DNA of P. putida KF715 was cloned and its nucleotide sequence analyzed. The enzyme gene was c omposed of 924 base pairs with ATG initiation codon and TCA terminatio n codon, which can encode a polypeptide of molecular weight 35 kDa con taining 307 amino acids. A promoter-like sequence and a ribosome-bindi ng sequence were identified upstream the enzyme gene. A deduced amino acid sequence of the catechol 2,3-dioxygenase exhibited 94% identity w ith that of corresponding enzyme in TOL plasmid and 25% identity with that of 2,3-dihydroxybipheny1 1,2-dioxygenase from the same strain. Fu rthermore, sequence comparison of the catechol 2,3-dioxygenase with ot her extradiol-type dioxygenases has led to identify evolutionally cons erved amino acid residues whose possible catalytic roles are proposed. (C) 1996 Academic Press, Inc.