In vivo construction of a hybrid pathway for metabolism of 4-nitrotoluene in Pseudomonas fluorescens

Pseudomonas fluorescens 410PR grows on 4-nitrobenzoate but does not metabolize 4-nitrotoluene. The TOL pWW0 delta pm plasmid converts 4-nitrotoluene into 4-nitrobenzoate through its upper pathway, but it does not metabolize 4-nitrobenzoate. P. fluorescens 410PR(pWW0 delta pm) transconjugants were isolated and found to be able to grow on 4-nitrotoluene. This phenotype was stable after growth for at least 300 generations without any selective pressure. P. fluorescens 410PR(pWW0 delta pm) converted 4-nitrotoluene into 4-nitrobenzoate via 4-nitrobenzylalcohol and 4-nitrobenzaldehyde. 4-Nitrobenzoate was metabolized via 4-hydroxylaminobenzoate and finally yielded NH4+ and 3,4-dihydroxybenzoate, which was mineralized.