The bacterial strain Escherichia coli is a commonly used host system for commercial production of recombinant proteins.  The accumulation of acetate as a fermentation byproduct has been a significant problem because it retards cell growth, inhibits protein formation, and diverts carbon from biomass and protein product. Various approaches, including operating condition manipulation to limit glucose overfeeding and strain improvement using genetic engineering approaches, to reduce the formation and accumulation of acetate have been reported in the literature.  Our current approach to reducing acetate accumulation was to disable the phosphoenolpyruvate:sugar phosphotransferase system (PEP-PTS) by deleting the ptsHI operon in the wild-type E. coli strain GJT001.  In complex medium, the mutant strain, TC110 showed reduced acetate accumulation which resulted in a significant improvement in final OD.  We tested the strains for the production of model recombinant proteins such as green fluorescent protein (GFP) and b-galactosidase.  The TC110 strain had a 385-fold improvement in final volumetric productivity of GFP over GJT001 in shake flask cultures.  Similarly, TC110 had a 7.5-fold improvement in final volumetric productivity of b-galactosidase over GJT001.  Replacing LB with corn steep liquor medium also showed a 28-fold improvement in final volumetric production of GFP.  When tested in a batch bioreactor the volumetric production of GFP by the TC110 strain was 25-fold higher than the volumetric productivity of GJT001.  In summary, the ptsHI mutant of GJT001 resulted in reduced acetate accumulation, which led to significant improvements in recombinant protein production in both shake flask and batch bioreactor cultures.