2025/05/08 by Nicolas Kieffer, Alberto Hipólito, Laura Ortiz-Miravalles +10 · 1 voice · 2 citations
Environmental Science · Biochemistry, Genetics and Molecular Biology · #Bacteriophages and microbial interactions #Antibiotic Resistance in Bacteria #Vibrio bacteria research studies
paper · doi:10.1126/science.ads0915
openalex publication_date 2025/05/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
Integrons are bacterial genetic elements that capture, stockpile, and modulate the expression of genes encoded in integron cassettes. Mobile integrons (MIs) are borne on plasmids, acting as a vehicle for hundreds of antimicrobial resistance genes among key pathogens. These elements also carry gene cassettes of unknown function ( gcu s) whose role and adaptive value remain unexplored. In this work, we show that gcu s encode phage resistance systems, many of which are newly discovered. Bacteriophage resistance integron cassettes (BRiCs) can be combined and mixed with resistance cassettes to produce multiphage or drug and phage resistance. The fitness costs of BRiCs are variable and dependent on the genetic context and can be modulated by changing the order of cassettes in the array. Hence, MIs act as highly mobile, low-cost defense islands.