Spo0A regulates chromosome copy number during sporulation by directly binding to the origin of replication in Bacillus subtilis.

When starved, Bacillus subtilis cells can enter the developmental programme of endospore formation by activation of the master transcriptional regulator Spo0A. Correct chromosome copy number is crucial for the production of mature and fully resistant spores. The production and maintenance of one chromosome for the mother cell and one copy for the forespore requires accurate co-ordination between DNA replication and initiation of sporulation. Here, we show that Spo0A regulates chromosome copy number by directly binding to a number of Spo0A binding sites that are present near the origin of replication (oriC). We demonstrate that cells lacking three specific Spo0A binding sites at oriC display increased chromosome copy numbers when sporulation is induced. Our data support the hypothesis that Spo0A directly controls DNA replication during sporulation by binding to oriC.

Boonstra M ，de Jong IG ，Scholefield G ，Murray H ，Kuipers OP ，Veening JW ... -  《-》

Spo0A, the key transcriptional regulator for entrance into sporulation, is an inhibitor of DNA replication.

Castilla-Llorente V ，Muñoz-Espín D ，Villar L ，Salas M ，Meijer WJ ... -  《-》

Spo0A links de novo fatty acid synthesis to sporulation and biofilm development in Bacillus subtilis.

During sporulation in Bacillus subtilis, the committed-cell undergoes substantial membrane rearrangements to generate two cells of different sizes and fates: the mother cell and the forespore. Here, we demonstrate that the master transcription factor Spo0A reactivates lipid synthesis during development. Maximal Spo0A-dependent lipid synthesis occurs during the key stages of asymmetric division and forespore engulfment. Spo0A reactivates the accDA operon that encodes the carboxylase component of the acetyl-CoA carboxylase enzyme, which catalyses the first and rate-limiting step in de novo lipid biosynthesis, malonyl-CoA formation. The disruption of the Spo0A-binding box in the promoter region of accDA impairs its transcriptional reactivation and blocks lipid synthesis. The Spo0A-insensitive accDA(0A) cells were proficient in planktonic growth but defective in sporulation (σ(E) activation) and biofilm development (cell cluster formation and water repellency). Exogenous fatty acid supplementation to accDA(0A) cells overcomes their inability to synthesize lipids during development and restores sporulation and biofilm proficiencies. The transient exclusion of the lipid synthesis regulon from the forespore and the known compartmentalization of Spo0A and ACP in the mother cell suggest that de novo lipid synthesis is confined to the mother cell. The significance of the Spo0A-controlled de novo lipid synthesis during B. subtilis development is discussed.

Pedrido ME ，de Oña P ，Ramirez W ，Leñini C ，Goñi A ，Grau R ... -  《-》

Evidence that metabolism and chromosome copy number control mutually exclusive cell fates in Bacillus subtilis.

Chai Y ，Norman T ，Kolter R ，Losick R ... -  《-》

DNA-related conditions controlling the initiation of sporulation in Bacillus subtilis.

Ireton K ，Grossman AD 《-》