Review on type 3 and type 5 secretion systems

In their recently published review, Rachel Whelan, Gareth McVicker and Jack C. Leo from the AROM group delve into the relationship between type 3 secretion systems (T3SSs) and type 5 secretion systems (T5SSs), providing an in-depth analysis of their roles in adhesion, invasion and their collaborative role in pathogenesis in Gram-negative bacteria. T3SSs form a syringe-like structure able to transport effector proteins into the host cell. T5SSs, also referred to as autotransporters, are known for their independent transport to the bacterial cell surface where they carry out a diverse array of functions, ranging from adhesion to immune evasion. This review discusses the interplay between the T3SSs and T5SSs that aid pathogenesis of some of the most well studied enteropathogenic organisms such as the Yersiniae, Shigella spp., enteropathogenic Escherichia coli and enterohaemorrhagic E. coli. The pathogenesis of these organisms relies heavily on the two secretion systems acting collectively to achieve virulence, resulting in host cell invasion, intra- and inter-cellular motility and evasion of the immune response, leading to changes in the host cell cytoskeleton which is central to disease.

Whelan R, McVicker G, Leo JC. Staying out or going in? The interplay between type 3 and type 5 secretion systems in adhesion and invasion of enterobacterial pathogens. Int J Mol Sci. 2020;doi:10.3390/ijms21114102.