Phage and Toxigenic Escherichia coli

Phage therapy has served as a good alternative to antibiotics by using bacteriophages to treat various infections caused by bacteria. Equipped with world-leading technology platforms and professional scientific staff, Creative Biolabs provides strong support in the development of phage-related therapies against toxigenic Escherichia coli.

Introduction of Toxigenic Escherichia coli

Enterotoxigenic Escherichia coli (ETEC) is a pathogenic variant of Escherichia coli. The production of heat-labile (LT) and heat-stable (ST) enterotoxins relies on chromosomally-encoded secretion systems. LT is secreted by a type 2 secretion system, while ST is secreted by TolC outer membrane efflux protein. ETEC is the leading cause of cholera-like watery diarrhea and remains a major global health threat, especially in developing countries. ETEC is widely distributed in all resource-poor regions of the world. Although ETEC infection is usually self-limiting, the use of antibiotics can relieve symptoms.

Shigatoxigenic Escherichia coli (STEC), also known as Verotoxigenic Escherichia coli (VTEC) is the strain of the bacterium Escherichia coli that produces Shiga toxin or Vero toxins. STEC is the most common food-borne zoonotic pathogen that results in multiple diseases, such as gastrointestinal illnesses, hemolytic uremic syndrome (HUS), and hemorrhagic colitis (HC). Till now, a series of strains of STEC have been identified, including E. coli O111 and E. coli O157.

Fig.1 Scheme of the signaling cascade in EHEC.

Shiga toxin-converting Bacteriophages

Shiga toxin-converting bacteriophages, also known as Stx phages, refer to the phages that carry the Shiga toxin genes. Stx phages play important roles in the dissemination of Shiga toxin genes, the emergence of new STEC strains, and the regulation of Shiga toxin production. The production of Shiga toxin occurs only after induction by Stx phage. Therefore, in the treatment of STEC infection, many antibiotics cause phage induction and are thus limited. Till now, all known Stx phages are double-stranded DNA-phages that belong to the group of lambdoid phages. As one of the best-studied E. coli phages, its functional genetic organization is similar to that of the prototypical lambda phage and all Stx phages share the same lambda-like genetic structures.

In years of research, Stx phages represent an important tool to better elucidate the distribution and role of phages in the host and their contribution to the treatment of human disease.

Fig.2 Influence of Stx prophages on the bacterial host transcriptome. (Rodríguez-Rubio, et al., 2021)

To fill the gaps in this field of phage therapy, Creative Biolabs offers the most advanced and comprehensive phage-related services today. We work to amplify your success in a highly collaborative manner. If you are interested in learning more about phages and toxigenic Escherichia coli, please do not hesitate to contact us for detailed information.

Reference:

1. Rodríguez-Rubio, L.; et al. Bacteriophages of Shiga toxin-producing Escherichia coli and their contribution to pathogenicity. Pathogens. 2021, 10(4): 404.