Sporulation during Growth in a Gut Isolate of Bacillus subtilis

• Tipo: Artigo em Revista Científica Internacional
• Data: 2014

Autores

Claudia Alexandra dos Reis Serra (Autor) FCUP; Earl, AM (Autor) Outra; Barbosa, TM (Autor) Outra; Kolter, R (Autor) Outra; Henriques, AO (Autor) Outra

Revista

Título: Journal of Bacteriology

Vol. 196

Páginas: 4184-4196

ISSN: 0021-9193

Editora: American Society for Microbiology

Indexação

ISI Web of Knowledge - 39 Citações

Scopus - 43 Citações

Outras Informações

ID Authenticus: P-009-YD6

DOI: 10.1128/jb.01993-14

Abstract (EN): Sporulation by Bacillus subtilis is a cell density-dependent response to nutrient deprivation. Central to the decision of entering sporulation is a phosphorelay, through which sensor kinases promote phosphorylation of Spo0A. The phosphorelay integrates both positive and negative signals, ensuring that sporulation, a time- and energy-consuming process that may bring an ecological cost, is only triggered should other adaptations fail. Here we report that a gastrointestinal isolate of B. subtilis sporulates with high efficiency during growth, bypassing the cell density, nutritional, and other signals that normally make sporulation a post-exponential-phase response. Sporulation during growth occurs because Spo0A is more active per cell and in a higher fraction of the population than in a laboratory strain. This in turn, is primarily caused by the absence from the gut strain of the genes rapE and rapK, coding for two aspartyl phosphatases that negatively modulate the flow of phosphoryl groups to Spo0A. We show, in line with recent results, that activation of Spo0A through the phosphorelay is the limiting step for sporulation initiation in the gut strain. Our results further suggest that the phosphorelay is tuned to favor sporulation during growth in gastrointestinal B. subtilis isolates, presumably as a form of survival and/or propagation in the gut environment.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 13