Bacillus cereus Certhrax ADP-ribosylates vinculin to disrupt focal adhesion complexes and cell adhesion [Cell Biology]

February 26th, 2014 by Simon, N. C., Barbieri, J. T.

Bacillus cereus (Bc) is often associated with mild to moderate gastroenteritis; however, some recent isolates cause inhalational anthrax-like diseases and death. These potential emerging human pathogens express multiple virulence factors. Bc strain G9241 expresses anthrax toxin, several polysaccharide capsules, and the novel ADP-ribosyltransferase, Certhrax. In this study, we show that Certhrax ADP-ribosylates R433 of vinculin, a protein that coordinates actin cytoskeleton and extracellular matrix interactions. ADP-ribosylation of vinculin disrupted focal adhesion complexes and redistributed vinculin to the cytoplasm. Exogenous vinculin rescued these phenotypes. This provides a mechanism for G9241 to breach host barrier defenses and promote bacterial growth and spread. Certhrax is the first bacterial toxin to add a post-translational modification to vinculin to disrupt the actin cytoskeleton.