The Pseudomonas putida KT2440 TOL upper pathway is repressed under nonlimiting conditions in cells growing in chemostat with succinate as a carbon source. We show that the ptsN gene product IIANtr participates in this repression. Crc, involved in yeast extract-dependent repression in batch cultures, did not influence expression when cells were growing in a chemostat with succinate at maximum rate.This work was supported by European Communities grant QLK3- CT-2002-01923, grant BCM 2001-0515 from the Spanish Ministry of Science and Education, and grant VEM2004-08560 from Spanish Ministry of the Environment.Peer reviewed