The process of bacterial secretion is integral to the life cycle of bacteria and the virulence of pathogenic bacteria. Under the umbrella of this funding initiative, we propose an interdisciplinary research program at the interface of biochemistry, microbiology, structural biology and biophysics to dissect the molecular basis of type II secretion in two most important opportunistic human pathogens: Pseudomonas aeruginosa and Burkholderia cenocepacia.