MdpJ fits in the phthalate (group 1) of aromatic ring hydroxylating dioxygenases. Sequences were aligned, and the tree was generated using the Bioedit 7.0.0 package (19). Representative α subunit sequences are from the following organisms/dioxygenase systems: MdpJ, proposed TBA hydroxylase M. petroleiphilum PM1 (ZP_00241560); B4 BphA1, BPDO, Pseudomonas sp. strain B4 (AJ251217); DBO1 OphA2, phthalate dioxygenase, B. cepacia DBO1 (AF095748); POB310 PobA, phenoxybenzoate dioxygenase, P. pseudoalcaligenes POB310 (X78823); PYR-1 PhtAa, phthalate dioxygenase, Mycobacterium vanbaalenii PYR-1 (AY365117); RB50_PobA, iron-sulfur protein, Bordetella bronchiseptica RB50 (CAE34653); RP007 PhnAc, polycyclic aromatic hydrocarbon dioxygenase: Burkholderia sp. strain RP007 (AF061751); TH2 CbdA, 2-halobenzoate dioxygenase, Burkholderia sp. strain TH2 (AB035324).