Outer membrane and secreted proteins in Gram-negative bacteria constitute a high percentage of virulence factors that are critical in disease initiation and progression. Despite their importance， it is often difficult to study these proteins due to challenges with expression and purification. Here we present a suite of vectors for the inducible expression of N-terminally 6His-tagged outer membrane， periplasmic， and secreted proteins in E. coli and show this system to be capable of producing milligram quantities of pure protein for downstream functional and structural analysis. This system can not only be used to purify recombinant virulence factors for structural and functional studies but can also be used to create gain-of-function E. coli for use in phenotypic screens， and examples of each are provided herein.