Alanine production by escherichia coli through metabolic engineering

by 1976- Lee, Mingtau

Alanine production in E. coli mutants expressing alanine dehydrogenase was studied. In aerobic production of alanine, different agitation speeds were compared: 150 rpm, 250 rpm, 350 rpm, 500 rpm, and 750 rpm. Two E. coli strains were studied: PRS 181 and ALS 890. It was found that more alanine was produced at lower agitation speeds. In anaerobic production of alanine, 3 different pH levels were compared: 7.0, 7.5, and 8.0. E. coli strain PRS 178 was studied. It was found that pH 7.5 was the best for alanine production. These observations suggest that more glucose could be directed into aerobical production of alanine at lower agitation speeds. pH was found to be an important factor of anaerobic alanine production.