Pathogen competitive exclusion

Pathogen competitive exclusion is not a specific molecule or receptor, but rather a biological phenomenon where beneficial microorganisms—such as probiotics—prevent pathogenic microbes from establishing themselves in an environment like the gut. This occurs primarily through competition for limited resources such as nutrients and physical space, making it difficult for harmful bacteria to adhere to host tissues and multiply[1][3]. The process can also involve antagonistic mechanisms, such as the production of antimicrobial substances or depletion of essential ions required by pathogens[8]. In applied settings, this principle is used in food safety and animal health—for example, introducing probiotic strains into poultry to reduce Salmonella colonization[3]. While highly relevant in infection control and microbiome management, "pathogen competitive exclusion" does not refer to a discrete molecular target suitable for drug binding or direct therapeutic modulation; instead, it describes an ecological interaction among microbial populations. Note: This entry is considered incorrect as a therapeutic target because it refers to a process/mechanism rather than a defined molecular entity like an enzyme or receptor.

Other names

Competitive exclusionCompetitive displacementGause's law (when referring to the ecological principle)

Competition for nutrients and space by beneficial microbes (e.g., probiotics) prevents pathogens from adhering to host tissues and proliferating[1][3][8]. Antagonism through production of antimicrobial compounds or depletion of essential ions (e.g., manganese scavenging by Lactobacillus)[3][8].