Colonization Capabilities of Environmental Pseudomonads and an Escherichia coli Intestinal Isolate in Two Different Continuous-Flow Models of the Murine Intestinal Tract

Abstract

In vitro continuous flow culture systems have been developed to test microorganisms for their potential to colonize the intestinal tract. Survival of two Pseudomonas aeruginosa strains, a Xanthomonas maltophilia strain, and an Escherichia coli strain was monitored in single-stage and two-stage continuous cultures of mouse caecal bacteria. Comparisons were made between their survival in vitro and in previous mouse dosing studies. Colonization resistance of the continuous flow models resulted in elimination of all four strains at a rate similar to, or faster than the washout rate. Neither in vitro system was able to reproduce in vivo findings with regard to the colonization capabilities of these microorganisms with potential for use as biotechnology agents.