Previous works showed that bacteria encoding capsules are better colonizers and are dominant in most environments suggesting a positive role for capsules in the genetic diversification of bacteria. Yet, it has been repeatedly suggested, based almost exclusively on studies in few model species, that such bacteria are less diverse and engage in fewer genetic exchanges. Here, we reverse the current paradigm and show that bacteria encoding capsules have larger and more diverse gene repertoires, which change faster by horizontal gene transfer and recombination.
Further, although the capsule increases the basal levels of tolerance to antibiotics, genomes encoding for capsules, also encode more antibiotic resistance genes.
Our study alters the traditional view of the capsule as a barrier to gene flow and raises novel questions in the role of capsules in bacterial adaptation.
For more info: https://doi.org/10.1371/journal.pgen.1007862