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Pseudomonas sp. strain RW611 utilized the ammonium salt of 2-sulfobenzoate as sole source of carbon, sulfur, nitrogen, and energy. The xenobiotic sulfo substituent was dioxygenolytically eliminated as sulfite, which was then slowly oxidized to sulfate. 2,3-Dihydroxybenzoate, which resulted from desulfonation underwent meta-cleavage, mediated by 2,3-dihydroxybenzoate 3,4-dioxygenase activity. This enzyme was inhibited by 3-chlorocatechol and 2,3,4-trihydroxybenzoate.

The dibenzofuran-degrading bacterial strain Pseudomonas sp. HH69 showed high oxidative activity towards 3-chlorodibenzofuran (3CDF). During the co-metabolic turnover of 3CDF large amounts of 4-chlorosalicylate and temporarily small amounts of salicylate were excreted. Simultaneously a yellow colour appeared due to the excretion of two polar products. Conversion of 3CDF by a mutant, derived from Pseudomonas sp. HH69 and defective in 2,3-dihydroxybiphenyl-1,2-dioxygenase led to the formation of equal quantities of 4′-chloro-2,2′,3-trihydroxybiphenyl (4′ CTHBP) and 4-chloro-2,2′,3-trihydroxybiphenyl (4CTHBP). Crude extracts of the wild type transformed 4′ CTHBP to 4-chlorosalicylate, whilst 4CTHBP was transformed to salicylate. Hence, we propose a non-selective initial attack on both aromatic rings of 3CDF and a degradative pathway for the resulting chlorotrihydroxybiphenyls.

A Pseudomonas sp. strain JWS was isolated from an enrichment culture with 3,5-dichlorosalicylate as the sole source of carbon and energy. Additionally, 3-chloro-, 5-chloro-, and 3,5-dibromosalicylate, but not 4-chlorosalicylate were mineralized by the organism. During growth on the chlorosalicylates, stoichiometric amounts of chloride were released into the culture medium. In the presence of both salicylate and 3,5-dichlorosalicylate, high activities were induced for the turnover of non-halogenated as well as halogenated salicylates. Enzyme activities assayed in crude cell extracts which are responsible for the oxidation of catechol and its halogenated derivatives as well as those for cycloisomerization of cis,cis-muconate and its 2,4-dichloro derivative provided indications for the involvement of inducible type II catechol 1,2-dioxygenase and muconate cycloisomerase in biodegradation of halogenated salicylates.