Cannibalism enhances biofilm development in Bacillus subtilis.
Cannibalism is a mechanism to delay sporulation in Bacillus subtilis. Cannibal cells express the skf and sdp toxin systems to lyse a fraction of their sensitive siblings. The lysed cells release nutrients that serve to feed the community, effectively delaying spore formation. Here we provide evidence that the subpopulation of cells that differentiates into cannibals is the same subpopulation that produces the extracellular matrix that holds cells together in biofilms. Cannibalism and matrix formation are both triggered in response to the signalling molecule surfactin. Nutrients released by the cannibalized cells are preferentially used by matrix-producing cells, as they are the only cells expressing resistance to the Skf and Sdp toxins. As a result this subpopulation increases in number and matrix production is enhanced when cannibalism toxins are produced. The cannibal/matrix-producing subpopulation is also generated in response to antimicrobials produced by other microorganisms and may thus constitute a defense mechanism to protect B. subtilis from the action of antibiotics in natural settings.
Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, MA 02115, USA.
Daniel
D
López
Hera
H
Vlamakis
Richard
R
Losick
Roberto
R
Kolter
D000222:Adaptation, Physiological / Q000235:genetics; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001412:Bacillus subtilis / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D001422:Bacterial Adhesion / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D018441:Biofilms / Q000254:growth & development*; D019149:Bioreactors; D004305:Dose-Response Relationship, Drug; D005109:Extracellular Matrix / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D005816:Genetic Complementation Test; D055666:Lipopeptides / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics; D050296:Microbial Viability / Q000235:genetics; D008954:Models, Biological; D011099:Polyglutamic Acid / Q000235:genetics; D011494:Protein Kinases / Q000235:genetics; D020543:Proteome / Q000235:genetics; D040901:Proteomics; D013171:Spores, Bacterial / Q000235:genetics / Q000254:growth & development / Q000502:physiology
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D055666:Lipopeptides; D008565:Membrane Proteins; D020543:Proteome; D011099:Polyglutamic Acid; D011494:Protein Kinases