Efflux Pump Deficient E. coli Platform

Figure 1 Normal E coli efflux pumps

Figure 1 Normal E coli efflux pumps


Researchers at the University of Guelph have developed a new in vitro research tool based on a mutant E. coli which is entirely deficient of efflux pumps. This viable organism is useful for evaluating one or all 35 bacterial efflux pumps which are critical components for bacteria to develop antibacterial agent resistance.
This isogenic genetically engineered Efflux KnockOut-35 “EKO-35” is a highly susceptible E. coli strain lacking all 35 efflux pumps (using inserted tandem stop codons). EKO-35 is physiologically viable when cultured under normal to optimal conditions. Any one or more of the 35 efflux pumps can be reactivated individually or in groups using pINT2 or pGDP-2 plasmids with constitutive PlacI promoter.
EKO-35 is also available with siderophore transporter FhuA to make EKO-35-Pore by adding commonly found “pores”, if needed for such studies.

Advantages and Applications

  • Necessary validation tool for any antibacterial drug development team
  • Ideal platform for studying individual efflux pumps in isolation to determine the fitness advantage provided by each pump
  • Ideal platform for studying the functionality and interplay between two or more
    specific efflux pumps in E coli
  • Loss of efflux pumps enhances biofilm formation – useful for study
  • EKO-35 can be used to study single component efflux pumps in combination with
    tripartite efflux systems or in combination with specific pores
  • EKO-35 represents an innovative tool kit to fully dissect the movement of
    compounds across the bacterial cell envelope
  • EKO-35 provides a unique opportunity to study desired combinations of efflux
    pumps and to probe the relationship between permeation and efflux
  • EKO-35 can also be used to study efflux pumps form other bacterial species
    using pump gene coded plasmids
  • EKO-35 can be used to assess drug-pump specificities and redundancies during
    new antibacterial agent development


Research Status: Ph.D. research completed
Development Status: Laboratory validation - TRL-4
Patent Status: Applications pending – US 63/352,569
License Status: Available for licensing


GenBank whole genome sequence of EKO-35:

Teelucksingh et al., 2022. A genetic platform to investigate the functions of bacterial
drug efflux pumps, Nature Chemical Biology Vol 18, pages1399–1409 (2022).

Goetz et al., 2022. Exploring functional interplay amongst Escherichia coli efflux pumps,
Microbiology; Vol 168, Issue 11. https://doi.org/10.1099/mic.0.001261


For licensing opportunities, contact:
David Hobson, DVM, DVSc, PEng, Manager, Technology Transfer & Entrepreneurship
dhobson@uoguelph.ca, 519-824-4120 Ext. 58859

For scientific inquiries, contact:
Dr Georgina Cox, PhD, Associate Professor, Molecular & Cellular Biology
gcox@uoguelph.ca, 519.824.4120 x54991