Catechol alternative ring fission

The degradation of salicylate to catechol is initiated by monooxygenation accompanied by decarboxylation (salicylate-l-hydroxylase), and two different and independent salicylate hydroxylases have been found in the naphthalene-degrading Pseudomonas stutzeri ANIO (Bosch et al. 1999). Alternatively, in Rhodococcus sp. strain B4, salicylate is hydroxylated to 2,5-dihydroxybenzoate by salicylate-5-hydroxylase (Grand et al. 1992). An alternative occurs for 5-hydroxy- and 5-aminosalicylate in Pseudaminobacter salicylatoxidans in which ring fission is accomplished directly (Hintner et al. 2001). 

For 3-chlorobenzoate, an alternative pathway in Alcaligenes sp. strain BR60 may involve 3,4- or 4,5-dioxygenation. Ring fission of the catechols resulted in the production of pyruvate and oxalacetate (Nakatsu and Wyndham 1993). 

The aerobic degradation of phenols is initiated by monooxidation with the production of catechols that undergo ring fission. A nnmber of stndies have used various strains of Rhodococcus sp. and Mycobacterium sp. to examine the metabolism of fluorinated phenols, and have illustrated important alternatives ... 

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