Appl.Environ.Microbiol.,vol61(6), 2211- 2217, 1995

Combination of the tod and the tol Pathways in Redesigning a Metabolic Route of Pseudomonas putida for the Mineralization of a Benzene, Toluene, and p-Xylene Mixture

Jang-Young Lee, Kwan-Hye Jung, Sang-Ho Choi and Hak-Sung Kim

Construction of a hybrid strain which is capable of mineralizing components of a benzene, toluene, and p-xylene mixture simultaneously was attempted by redesigning the metabolic pathway of Pseudomonas putida. Genetic and biochemical analysis of the tod and the tol pathays revealed that dihydrodiols formed from benzene, toluene, and p-xylene by toluene dioxygenase in the tod pathway could be channeled into the tol pathway by the action of cis-p-toluate-dihydrodiol dehydrogenase, leading to complete mineralization of a benzene, toluene, and p-xylene mixture. Consequently, a hybrid strain was comstructed by cloning todC1C2BA genes encoding toluene dioxygenase on RSF1010 and introducing the resulting plasmid into P. putida mt-2. The hybrid strain of P. putida TB105 was found to mineralize a benzene, toluene, and p-xylene mixture without accumulation of any metabolic intermediate.