A succinimide-assimilating bacterium, Pseudomonas putida s52, was found to be a potent producer of pyruvate from fumarate. Using washed cells from P. putida s52 as catalyst, 400 mM pyruvate was produced from 500 mM fumarate in a 36-h reaction. Bromopyruvate, a malic enzyme inhibitor, was used for the selection of mutants with higher pyruvate productivity. A bromopyruvate-resistant mutant, P. putida 15160, was found to be an effective catalyst for pyruvate production. Moreover, under batch bioreactor conditions, 767 mM of pyruvate was successfully produced from 1,000 mM fumarate in a 72-h reaction with washed cells from P. putida 15160 as catalyst.