Recombinat protein production in high-cell density cultures of E. coli strains with defective glucose uptake capacity

Through the carbohydrate transport engineering we were able to improve recombinant protein production in E. coli strains. Those strains have defective glucose transport due the deletion of genes that encodes PTS and non-PTS transport systems. The first approach was performed in minimal medium using glucose as carbon and energy source. However, it its was our interest to test some strains in high-cell density cultures, which are more similar to industrial bioprocesses. In this work we have tested an E. coli strains lacking ptsHIcrr and mglABC operons, carring a plasmid which encodes a soluble GFP protein in a medium which contains glucose 100 g/L and yeast extract 50 g/L in totally aerobic conditions.