Several C4 compounds, such as malate, succinate and fumarate, are widely used by the industry to produce synthetic resins, food additives, pharmaceuticals and other chemicals.Currently, their production is mainly accomplished by chemical processes using petroleum derivatives as starting materials, these processes could lead to pollution and to a potential shortage in the future. On the other hand, the bacteria Escherichia coli synthesize some of these compounds naturally but with poor product yields. We will present metabolic engineering approaches to modify E. coli metabolic pathways to increase product yields with the purpose of developing a fermentation process from renewable feedstocks (“green technology”) with the potential to replace the traditional petrochemical processes.