Production of L-phenylalanine from phenylpyruvate using resting cells of Escherichia coli

Summary We describe the production of L-phenylalanine from phenylpyruvate using resting cells of a genetically modified strain of Escherichia coli. Fermentations were carried out by continuously raising the feeding rate of D-glucose. We reached a biomass of 10 g/l dry weight and an aminotransferase activity of 14000 U/l The maximum phenylalanine concentration achieved was 173 mmol/l with a phenylpyruvate molar conversion yield of 95%.Dedicated to Prof. Dr. Heinz Harnisch on the occasion of his 60th birthday