Abstract

The ability to utilize agricultural waste products is one of the many reasons why bioprocessing using Escherichia coli is an attractive alternative to unsustainable fossil fuel-based methods for chemical synthesis. However, mixed sugar co-utilization is a challenge for E. coli due to the effects of carbon catabolite repression (CCR), which dictates a preference for the consumption of glucose over secondary sugars through the mechanisms of inducer exclusion and transcriptional regulation. To overcome these obstacles, metabolic engineers have developed strategies to relax the effects of CCR through both global and sugar-specific methods. Understanding the feed conditions as well as the engineering opportunities for CCR relaxation can allow for the development of a strain with maximized productivity and growth.