Live‐Cell Fluorescent Visualization of T3SS Needle and Its Dynamics

Abstract

The Type III Secretion System (T3SS) is a complex transmembrane apparatus used by many Gram‐negative pathogens for protein translocation and host invasion. An essential T3SS component is the needle, a hollow substructure extending from the bacterial membrane, spanning the space from the bacterium to the host cytosol. The needle is formed by helical polymerization of a single small protein, which is secreted by the T3SS and assembled outside the bacterium. Visualization of the needle previously depended on immunofluorescence, which requires cell fixation. We hereby describe a simple methodology for T3SS needle fluorescent tagging and visualization, which enables live‐cell microscopy and investigation of needle kinetics and dynamics.Support or Funding InformationThis study was supported in part by the DAAD RISE Scholarship, Reed College Biology Undergraduate Student Travel Award, Reed College Summer Opportunity Fellowship, Reed College Undergraduate Research Opportunity Grant and Galakatos funds.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.