Bacillus subtilis utilizes the DNA damage response to manage multicellular development.

Area of Science:

• Microbiology
• Bacterial Physiology
• Molecular Biology

Background:

• Bacteria form biofilms, a multicellular state crucial for survival and pathogenesis.
• Environmental and cellular cues regulate biofilm development.
• It is widely believed that stress promotes biofilm formation for protection.

Purpose of the Study:

• To investigate the influence of cellular and environmental DNA damage on biofilm formation.
• To elucidate the mechanism by which DNA damage affects biofilm development in *Bacillus subtilis*.

Main Methods:

• Induction of oxidative DNA damage in *Bacillus subtilis* cultures.
• Analysis of gene expression related to matrix production and DNA damage response (DDR).
• Microscopic examination of cell differentiation and spatial organization within biofilms.

Main Results:

• Oxidative DNA damage prevents biofilm formation and cell differentiation in *B. subtilis*.
• Reactive oxygen species accumulation triggers the DNA damage response (DDR).
• DDR activation suppresses matrix gene expression, leading to spatially separated DDR-ON cells and matrix producers, mediated by the Sda protein.

Conclusions:

• DNA damage acts as an anti-biofilm signal in *B. subtilis*.
• A novel survival strategy involves DDR-mediated separation from the biofilm community.
• This mechanism allows individual cells to escape a potentially harmful multicellular environment.