Molecular cloning and analysis of the aroD gene encoding 3-dehydroquinate dehydratase from Corynebacterium glutamicum

Abstract

The aroD gene was cloned from Corynebacterium glutamicum by complementation of Escherichia coli aromatic amimo acid auxotroph. The E. coli aroD gene codes for 3-dehydroquinte dehydratase (dehydroquinase), an enzyme involved in the aromatic amino acid biosynthesis pathway. The cloned insert DNA fragments in the recombinant plasmids, named pROD5, pROD8, and pROD14, were physically mapped with several restriction endonucleases. We determined the DNA nucleotide sequences of the fragment and reported here the sequences of the aroD gene. The complete nucleotide sequences of the aroD gene showed an open reading frame encoding a protein of 145 amino acids with a deduced molecular weight of about 16 kDa. Comparison of this deduced amino acid sequences of C. glutamicum aroD gene with those of the enzyme from Pseudomonas aeruginosa, Mycobacterium tuberculosis and Actinobacillus pleuropneumonia revealed 51%, 53% and 54% similarity, respectively.