Localization of naphthalene degradation genes in P. naphthalenivorans strain CJ2. (A) Plasmids retrieved from wild-type CJ2 and two positive-control pseudomonads carrying 80-kb naphthalene catabolic plasmids, P. putida NCIB 9816-4 and P. putida G7; (B) Southern hybridization of plasmids with nahAc probes; (C) the genomic DNA from strain CJ2 digested with HindIII, EcoRI, KpnI, and XbaI; (D) Southern hybridization of the digested genomic DNA with nahAc probes; M, molecular size marker, λ-DNA digested with HindIII.