DEGRADATION OF 2-CHLOROBENZOIC AND 2,5-DICHLOROBENZOIC ACIDS IN PURE CULTURE BY PSEUDOMONAS-STUTZERI

A strain of Pseudomonas stutzeri KS25 utilizing 2-chlorobenzoic and 2, 5-dichlorobenzoic acids as the sole carbon and energy source was isola ted from polychlorophenol-contaminated soil and sewage, using the meth od of enrichment cultures. This strain was also able to grow on 2-fluo ro-, 2-iodo-, 2-bromo- and 2,5-dihydroxybenzoate, but did not utilize 3-, 4-chloro-, 2,4- and 2,6-dichlorobenzoates as the sole carbon and e nergy source, however, it cometabolized 3-chloro-, 2,4- and 2,6-dichlo robenzoates, but not 4-chlorobenzoate. The yield of released chlorine during utilization of 2-chloro- and 2,5-dichlorobenzoates amounted to 100 % of the theoretical. The concentration of 2-chloro- and 2,5-dichl orobenzoates, not substantially inhibiting the isolated microorganism, was within the range 0.25-0.5 and 2.5-3.0 g/L, respectively.