Comparison of paa gene organizations in Rhodococcus sp. strain RHA1 and other bacteria. The gene names are in accordance with those listed in reference 12. Tn, transposase; TetR, TetR family regulator; paaR, an AraC-type regulator. Variants of paa genes are indicated with a prime (e.g., C′, A′, and D′). All sequences, except that of RHA1, were obtained from The Institute for Genomic Research (http://www.tigr.org/tdb) or NCBI (http://www.ncbi.nlm.nih.gov).