EngineeringEscherichia colito utilize erythritol as sole carbon source

Abstract

AbstractErythritol, one of the natural sugar alcohols, is widely used as a sugar substitute sweetener in food industries. Human themselves are not able to catabolize erythritol and their gut microbes lack related catabolic pathways either to metabolize erythritol. Here, we engineerEscherichia colito utilize erythritol as sole carbon source aiming for defined applications. First, we isolate the erythritol metabolic gene cluster and experimentally characterize the erythritol-binding transcriptional repressor and its DNA-binding site. Transcriptome analysis suggests that carbohydrate metabolism-related genes in the engineeredE. coliare overall upregulated, which then guides the selection of four genes for overexpression that notably enhances cell growth. Finally, engineeredE. colistrains can be used as a living detector to distinguish erythritol-containing soda soft drinks and can grow in the simulated intestinal fluid supplemented with erythritol. We expect our work will inspire the engineering of more hosts to respond and utilize erythritol for broad applications in metabolic engineering, synthetic biology, and biomedical engineering.