Regulation of the SOS response and homologous recombination by an integrative and conjugative element

2024/10/12 by Alam García Heredia, Alan D. Grossman · 1 voice
Biochemistry, Genetics and Molecular Biology · #Bacterial Genetics and Biotechnology #DNA Repair Mechanisms #RNA and protein synthesis mechanisms

paper · pdf · doi:10.1101/2024.10.11.617942

openalex publication_date 2024/10/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01

Abstract

Abstract Integrative and conjugative elements (ICEs) are mobile genetic elements that transfer between bacteria and influence host physiology and promote evolution. ICE Bs1 of Bacillus subtilis modulates the host DNA damage response by reducing RecA filament formation. We found that the two ICE Bs1 -encoded proteins, RamT and RamA that modulate the SOS response in donors also function in recipient cells to inhibit both the SOS response and homologous recombination following transfer of the element. Expression of RamT and RamA caused a decrease in binding of the host single strand binding protein SsbA to ssDNA. We found that RamA interacted with PcrA, the host DNA translocase that functions to remove RecA from DNA, likely functioning to modulate the SOS response and recombination by stimulating PcrA activity. These findings reveal how ICE Bs1 can modulate key host processes, including the SOS response and homologous recombination, highlighting the complex interplay between mobile genetic elements and their bacterial hosts in adaptation and evolution.

Citations

• Timing of integration into the chromosome is critical for the fitness of an integrative and conjugative element and its bacterial host

Discussions

• Though not fully elucidated here, this seems to differ from the mechanism utilized by PsiB encoded by F-plasmid as it is active in donors and is not believed to interact directly with RecA. Alam Hered [bsky, 0 points, 1 comments]

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