Evolution for elucidation of sugar uptake regulatory system of E. coli

E. coli that has been used as a model organism, an industrial workhorse, and even a probiotic, was originally discovered and isolated in the feces of human. For twenty years since the genome sequence of E. coli was firstly determined, the functional studies on the annotation of individual genes have been extensively carried out. However, many genes with unknown functions still remain. Although the natural habitat of E. coli is an anaerobic gut, the physiology and metabolism of E. coli have been substantially studied under aerobic conditions because of experimental convenience and manageability. Under anaerobic conditions with limited respiration, balanced redox potentials and ATP generation are key determining factors for cellular growth and viability. Our research team found that anaerobic metabolic and regulatory network can be brought to light by continuous adaptive mutations. In this project, anaerobic adaptations of sugar uptake mutants, and the characterization of their adapted progeny strains was carried out.