The type III secretion injectisome, a complex nanomachine for intracellular 'toxin' delivery.
The type III secretion injectisome is a nanomachine that delivers bacterial proteins into the cytosol of eukaryotic target cells. It consists of a cylindrical basal structure spanning the two bacterial membranes and the peptidoglycan, connected to a hollow needle, eventually followed by a filament (animal pathogens) or to a long pilus (plant pathogens). Export employs a type III pathway. During assembly, all the protein subunits of external elements are sequentially exported by the basal structure itself, implying that the export apparatus can switch its substrate specificity over time. The length of the needle is controlled by a protein that it also secreted during assembly and presumably acts as a molecular ruler.
Cornelis
Guy R
GR
Biozentrum der Universität Basel, CH-4056 Basel, Switzerland. guy.cornelis@unibas.ch
D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D058947:Bacterial Secretion Systems / Q000502:physiology*; D008854:Microscopy, Electron; D049329:Nanostructures / Q000737:chemistry*; D036103:Nanotechnology
D001426:Bacterial Proteins; D058947:Bacterial Secretion Systems