Clostridium difficile (C. diff) - associated disease of the gut is a major health problem, and current treatment methods are both ineffective and unpalatable. Previous research identified a C. diff-specific endolysin from the phage ΦCD27, which could be used to kill C. diff cells. Type VI secretions systems, found in a variety of organisms including Salmonella typhimurium, are characterised by a needle structure, the primary component of which is encoded by the gene Hcp. The tip of the needle is encoded by VgrG. The aim of this project was to create a new type of synthetic Escherichia coli expressing a simplified version of the Type VI Secretion System, with the C. diff-specific endolysin fused to VgrG, and which could be delivered to the gut to combat serious C. diff infections. Mathematical modelling was used to assist in the biological planning and a variety of relevant software applications were made.