Sequence Analysis of the Oxidase/Reductase Genes Upstream of the Rhodococcus Erythropolis Aldehyde Dehydrogenase Gene thcA Reveals a Gene Organisation Different from Mycobacterium Tuberculosis

Abstract

The sequence of the DNA region upstream of the thiocarbamate-inducible aldehyde dehydrogenase gene thcA of Rhodococcus erythropolis NI86/21 was determined. Most of the predicted ORFs are related to various oxidases/reductases, including short-chain oxidases/reductases, CMC oxidoreductases, α-hydroxy acid oxidases (subfamily 1 flavin oxidases/dehydrogenases), and subfamily 2 flavin oxidases/dehydrogenases. One ORF is related to enzymes involved in biosynthesis of PQQ or molybdopterin cofactors. In addition, a putative member of the TetR family of regulatory proteins was identified. The substantial sequence divergence from functionally characterized enzymes precludes a reliable prediction about the probable function of these proteins at this stage. In Mycobacterium tuberculosis H37Rv, most of these ORFs have homologs that are also clustered in the genome, but some striking differences in gene organization were observed between Rhodococcus and Mycobacterium.

Key Words:

• aldehyde dehydrogenase ThcA
• α-hydroxy acid oxidase
• GMC oxidoreductase
• flavin oxidase/dehydrogenase
• pyrroloquinoline quinone (PQQ)
• short chain oxidase/reductase