Bacillus subtilis biofilm extends Caenorhabditis elegans longevity through downregulation of the insulin-like signaling pathway

DONATO V.; RODRIGUEZ AYALA F.; COGLIATI S.; BAUMAN C.; COSTA J.G.; LEÑINI C.; GRAU R.

NATURE COMMUNICATIONS

Nature Publishing Group

Año: 2017 vol. 8

2041-1723

Of crucial interest are the mechanisms by which beneficial bacteria affect hostlongevity; however, these mechanisms remain unclear. Here we used the modelorganisms Bacillus subtilis and Caenorhabditis elegans to study how the bacterialbiofilm affects host longevity. Biofilm-proficient B. subtilis colonized the C. elegans gut and extended the worm lifespan significantly longer that did biofilm-deficient isogenic strains. In addition to biofilm proficiency, the quorum-sensing pentapeptide CSF and nitric oxide (NO) represent the entire B. subtilis repertoire responsible for the extended longevity of C. elegans. B. subtilis grown under biofilm-supporting conditions synthesized higher levels of NO and CSF than under planktonic growth conditions, emphasizing the key role of the biofilm in slowing host aging. Significantly, the prolongevity effect of B. subtilis was primarily under DAF-2/DAF-16/HSF-1 control, a finding that links extended lifespan to downregulation of the insulin-like signaling (ILS) pathway.