Aromatic degradation, ortho pathway

In a case analogous to the combination of the two plasmid encoded ortho- and mta-fission pathways in B13 for specific halo-aromatic utilization, another bacterium was modified with a hybrid pathway for this purpose. B. cepacia G4 degrades toluene, phenol, benzene, and ortho-cresol via a unique toluene ottfw-monooxygenase (Tom) pathway (Shields et al., 1989) encoded by the toluene catabolic plasmid TOM (Shields et al., 1995). 

The degradation of 2-chlorobenzoic acid by P. cepacia also involves removal of the chlorine substituents in the first step [121,122], but here the aromatic ring undergoes oxidation with elimination of CO,. Catechol, which is the first intermediate of this metaboHc pathway, is further degraded by an ortho-cleavage pathway. A metabolic pathway for the degradation of 3-chlorobenzoic acid by Pseudomonas sp. B13 is shown in Figure 4. Zaitsev and Baskunov [123] reported a similar scheme for the metabolism of 3-chlorobenzoic acid in Acinetobacter calcoaceticus. 

---