Pathogenic gut bacteria (Enterobacteriaceae)

Pathogenic gut bacteria, particularly members of the Enterobacteriaceae family such as Salmonella enterica and certain strains of Escherichia coli, represent a significant therapeutic challenge in the context of enteric infections and chronic inflammatory conditions like Inflammatory Bowel Disease (IBD) [1]. The therapeutic strategy involving microcins and competitive interactions leverages the natural ecological warfare between bacterial strains to selectively eliminate these pathogens [2]. Microcins are low-molecular-weight antimicrobial peptides produced by certain "good" bacteria, such as the probiotic E. coli Nissle 1917, which often utilize "Trojan horse" mechanisms by mimicking siderophores to gain entry into target cells via specific nutrient receptors like IroN or FepA [3]. Once inside, these microcins disrupt essential cellular processes like DNA replication, RNA transcription, or protein synthesis, leading to the death of the pathogen without harming the broader commensal microbiota [4]. This approach is particularly relevant in treating conditions where dysbiosis and pathogen overgrowth are prevalent, as it provides a narrow-spectrum alternative to traditional broad-spectrum antibiotics [5]. By exploiting the pathogen's own iron-acquisition systems, microcin-producing probiotics can effectively outcompete and displace harmful bacteria in the nutrient-limited environment of the inflamed gut [1]. Current research is focused on developing engineered probiotics and synthetic siderophore-microcin conjugates to enhance the efficacy and specificity of this competitive exclusion strategy [4].

Other names

Enteric pathogensDysbiotic gut microbiotaMicrocin-sensitive bacteriaInflammatory EnterobacteriaceaeGram-negative gut pathogens

Targeted elimination of pathogenic strains through competitive exclusion and the production of microcins that utilize pathogen-specific siderophore receptors for cellular entry and subsequent inhibition of vital metabolic processes [1, 3].