Bacterial natural transformation drives cassette shuffling and simplifies recombination in chromosomal integrons.

ABSTRACT: Integrons act as biobanks of gene cassettes conferring functions crucial for bacterial defense, including protection against phages and antibiotics. They enable bacterial on-demand adaptation through capture and shuffling of the cassettes under stress conditions. Our results underscore the significant role of horizontal gene transfer in integron cassette recombination. We discover that sedentary chromosomal integrons (SCIs), such as those found in Vibrio cholerae, efficiently excise and recruit cassettes from linear single-stranded DNA fragments acquired during natural transformation. We propose a simplified mechanism for the cassette excision process from this type of substrates, requiring only a single strand exchange at the attC recombination sites, ruling out any replicative mechanism.

SUBMITTER: Debatisse K 

PROVIDER: S-EPMC12614218 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature