Effects of glucose and phenylalanine upon 2,4,6-trichlorophenol degradation by Pseudomonas paucimobilis S37 cells in a no-growth state

Pseudomonas paucimobilis S37, a strain able to degrade 2,4,6-trichlorophenol (246-TCP), was isolated from an aquatic environment polluted with this compound. The effect of two natural organic compounds on the degradation of 246-TCP by this strain, in a no-growth state, was studied. Bacterial cultures were exposed to 0.1 mM and 0.5 mM of 246-TCP, alone, or in the presence of similar concentrations of glucose, a growth supporting substrate, or phenylalanine, a no-growth supporting compound. The effects on viable counts and 246-TCP degradation were measured. The bacterial culture died with 0.5 mM 246-TCP. This effect was overcome by the presence of glucose or phenylalanine, although no degradation of 246-TCP was detected. At 0.1 mM 246-TCP, the viability was not altered, and cells were able to degrade this compound. Glucose at 0.1 mM increased the degradative activity, but higher levels were inhibitory. Phenylalanine at 0.67 mM or higher concentration was also inhibitory of the 246-TCP degradation.