Pneumococcal pneumonia is driven by increased bacterial turnover due to bacteriocin-mediated intra-strain competition.

ABSTRACT: Using chromosomal barcoding, we observed that >97% of the Streptococcus pneumoniae (Spn) population turns over in the lung within 2 days post-inoculation in a murine model. This marked collapse of diversity and bacterial turnover was associated with acute inflammation (severe pneumococcal pneumonia), high bacterial numbers in the lungs, bacteremia, and mortality. Intra-strain competition mediated by the blp locus, which expresses bacteriocins in a quorum-sensing-dependent manner, was required for each of these effects. Bacterial turnover from the activity of Blp-bacteriocins increased the release of the pneumococcal toxin, pneumolysin (Ply), which was sufficient to account for the lung pathology. The ability of Ply to evade complement, rather than its pore-forming activity, prevented opson

SUBMITTER: Aggarwal SD 

PROVIDER: S-EPMC11621112 | biostudies-literature | 2024 Dec

REPOSITORIES: biostudies-literature