| Summary: | The intestinal carriage rates of <i>Pseudomonas aeruginosa</i> are notably elevated in immunosuppressed individuals and hospitalized patients, increasing the risk of infection and antibiotic-associated diarrhea. A potential solution to this issue lies in autonomous antibacterial therapy, remaining inactive until a pathogen is detected, and releasing antibacterial compounds on demand to eliminate the pathogen. This study focuses on the development of genetically engineered probiotics capable of detecting and eradicating <i>P. aeruginosa</i> by producing and secreting PA2-GNU7, a <i>P. aeruginosa</i>-selective antimicrobial peptide (AMP), triggered by the presence of <i>P. aeruginosa</i> quorum-sensing molecule <i>N</i>-(3-oxododecanoyl)-<sub>L</sub>-homoserine lactone (3OC<sub>12</sub>HSL). To achieve this goal, plasmid-based systems were constructed to produce AMPs in response to 3OC<sub>12</sub>HSL and secrete them into the extracellular medium using either the microcin V secretion system or YebF as a carrier protein. Following the transfer of these plasmid-based systems to <i>Escherichia coli</i> Nissle 1917 (EcN), we successfully demonstrated the ability of the engineered EcN to express and secrete PA2-GNU7, leading to the inhibition of <i>P. aeruginosa</i> growth in vitro. In addition, in a mouse model of intestinal <i>P. aeruginosa</i> colonization, the administration of engineered EcN resulted in reduced levels of <i>P. aeruginosa</i> in both the feces and the colon. These findings suggest that engineered EcN holds promise as a potential option for combating intestinal <i>P. aeruginosa</i> colonization, thus mitigating the risk of future endogenous infections in vulnerable patients.
|
|---|