Complement-mediated killing of Escherichia coli by mechanical destabilization of the cell envelope.

ABSTRACT: Complement proteins eliminate Gram-negative bacteria in the blood via the formation of membrane attack complex (MAC) pores in the outer membrane. However, it remains unclear how outer membrane poration leads to inner membrane permeation and cell lysis. Using atomic force microscopy (AFM) on living Escherichia coli (E. coli), we probed MAC-induced changes in the cell envelope and correlated these with subsequent cell death. Initially, bacteria survived despite the formation of hundreds of MACs that were randomly distributed over the cell surface. This was followed by larger-scale disruption of the outer membrane, including propagating defects and fractures, and by an overall swelling and stiffening of the bacterial surface, which precede inner membrane permeation. We conclude that bacterial

SUBMITTER: Benn G 

PROVIDER: S-EPMC11612287 | biostudies-literature | 2024 Dec

REPOSITORIES: biostudies-literature