Improved degradation of monochlorophenols by a constructed strain.

Pseudomonas sp. strain B13, a strain able to degrade 3-chlorobenzoate and, after prolonged adaptation (40 days), 4-chlorophenol, could transfer the ability to degrade chlorocatechols to a recipient, Alcaligenes sp. strain A7, which is able to grow with benzoate and phenol. Representative transconjugants, such as Alcaligenes sp. strain A7-2, were able to utilize all three isomeric chlorophenols; this property was not possessed by the donor or the recipient. The ability to grow readily with 4-chlorophenol may be attributable to a more rapid induction of phenol hydroxylase by Alcaligenes sp. strain A7-2 than by Pseudomonas sp. strain B13, a property which correlates with the greater level of resistance to chlorophenols shown by the transconjugant.