title: Cooperation and the evolutionary ecology of bacterial virulence: the Bacillus cereus group as a novel study system.
abstract: How significant is social evolution theory for the maintenance of virulence in natural populations? We assume that secreted, distantly acting virulence factors are highly likely to be cooperative public goods. Using this assumption, we discuss and critically assess the potential importance of social interactions for understanding the evolution, diversity and distribution of virulence in the Bacillus cereus group, a novel study system for microbial social biology. We conclude that dynamic equilibria in Cry toxin production, as well as strong spatial structure and population bottlenecks in hosts are the main ecological factors maintaining the cooperative secretion of virulence factors and argue that collective action has contributed to the evolution of narrow host range. Non-linearities in the benefits associated with public goods, as well as the lack of private secretion systems in the Firmicutes may also explain the prevalence and importance of distantly acting virulence factors in B. cereus and its relatives.
authors.affiliation: School of Biological Sciences, Royal Holloway University of London, Egham, UK. ben.raymond@rhul.ac.uk
authors.forename: Ben
authors.initials: B
authors.lastname: Raymond
authors.forename: Michael B
authors.initials: MB
authors.lastname: Bonsall
mesh_terms: D000818:Animals; D001408:Bacillus anthracis / Q000235:genetics / Q000472:pathogenicity; D001409:Bacillus cereus / Q000235:genetics / Q000472:pathogenicity*; D001413:Bacillus thuringiensis / Q000235:genetics / Q000472:pathogenicity*; D001419:Bacteria / Q000472:pathogenicity*; D001426:Bacterial Proteins; D005075:Biological Evolution; D047630:Depsipeptides / Q000737:chemistry; D017753:Ecosystem; D054884:Host-Pathogen Interactions; D006801:Humans; D019476:Insect Proteins / Q000502:physiology; D010802:Phylogeny; D053038:Quorum Sensing; D011956:Receptors, Cell Surface / Q000502:physiology; D014774:Virulence / Q000235:genetics*; D037521:Virulence Factors
chemical_list: D001426:Bacterial Proteins; C095416:Cry toxin receptors; D047630:Depsipeptides; D019476:Insect Proteins; D011956:Receptors, Cell Surface; D037521:Virulence Factors; C089294:cereulide
keywords: cooperation; host range; microbial ecology; social evolution; toxin; virulence