The ATPases of the mycobacterial type VII secretion system: structural and mechanistic insights into secretion

Publication date: Available online 22 November 2019Source: Progress in Biophysics and Molecular BiologyAuthor(s): Thomas D. Crosskey, Katherine S.H. Beckham, Matthias WilmannsAbstractTuberculosis (TB) remains the foremost cause of death by infectious disease and is propagated by the pathogen Mycobacterium tuberculosis (Mtb). The virulence associated with Mtb is mediated by proteins secreted into host cells by the type VII secretion system (T7SS), making this system a candidate for future drug and vaccine development. However, while many of the components involved in the T7SS have been identified, the mechanism of translocation across both the inner and outer mycobacterial membranes remains largely unexplained. Key to the translocation of proteins across the membrane is the activity of conserved AAA+ ATPases EccA and EccC, which are explored in this review. Although the T7SS does not appear homologous to other known bacterial secretion systems, many of those require ATPase activity during different phases of protein translocation. Thus, exploring the roles of ATPases in multiple secretion systems may provide insights into the T7SS. Targeting bacterial virulence factors such as secretion systems is becoming an increasingly explored area of research, and here we review how such strategies could be applied to the T7SS.
Source: Progress in Biophysics and Molecular Biology - Category: Molecular Biology Source Type: research