The effect of glucose on growth and degradation of caffeine by Pseudomonas sp.

The effect of glucose on caffeine degradation by Pseudomonas sp., which was previously isolated in our laboratory, was investigated. Caffeine degradation was inhibited when glucose was present in free form in the medium and at a concentration > 1 g L-1. Two-stage culture experiments indicated that glucose probably interferes with the induction of the enzymes involved in the caffeine degradation pathway. The addition of glucose at start and early stages of growth resulted in complete inhibition of caffeine degradation whereas addition at later stages of growth has no inhibitory effect further confirming the inhibitory effect of glucose is due suppression of caffeine catabolising enzyme, which is suggestive of catabolite repression. These findings are novel and have not been reported in other Pseudomonas peptide strains degrading caffeine. © 2007 Academic Journals.