Helical reconstruction of Salmonella and Shigella needle filaments attached to type 3 basal bodies

• DOI: 10.1016/j.bbrep.2021.101039
• Publication Date: 2021-06-27T06:08:22Z
• Authors: Vadim Kotov; Michele Lunelli; Jiri Wald; Michael Kolbe; Thomas C. Marlovits
• Keywords: Basal body

Gram-negative pathogens evolved a syringe-like nanomachine, termed type 3 secretion system, to deliver protein effectors into the cytoplasm of host cells. An essential component this system is long helical needle filament that protrudes from bacterial surface and connects cytoplasms bacterium eukaryotic cell. Previous structural research was predominantly focused on reconstituted filaments, which lacked biological context. In work we introduce facile procedure obtain high-resolution cryo-EM structure filaments attached basal body systems. We validate our approach by solving Salmonella PrgI demonstrate its utility obtaining first reconstruction Shigella MxiH filament. Our paves way systematic characterization in context mutagenesis studies, evolution drug development.