2024/12/13 by Ekaterina Vorobevskaia, Céline Loot, Didier Mazel +1 · 1 voice
Biochemistry, Genetics and Molecular Biology · #Bacterial Genetics and Biotechnology #Escherichia coli research studies #Lipid Membrane Structure and Behavior
paper · pdf · doi:10.1126/sciadv.adp8756
openalex publication_date 2024/12/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
Multiple antibiotic resistances are a major global health threat. The predominant tool for adaptation in Gram-negative bacteria is the integron. Under stress, it rearranges gene cassettes to offer an escape using the tyrosine recombinase IntI, recognizing folded DNA hairpins, the attC sites. Four recombinases and two attC sites form the synaptic complex. Yet, for unclear reasons, the recombination efficiency varies greatly. Here, we established an optical tweezers force spectroscopy assay to probe the synaptic complex stability and revealed, for seven combinations of attC sites, significant variability in the mechanical stability. We found a strong correlation between mechanical stability and recombination efficiency of attC sites in vivo, indicating a regulatory mechanism from the DNA structure to the macromolecular complex stability. Taking into account known forces during DNA metabolism, we propose that the variation of the integron in vivo recombination efficiency is mediated by the synaptic complex stability. We anticipate that further recombination processes are also affected by their corresponding mechanical stability.