Bacillus pumilus, a Gram-positive, aerobic, and spore-forming bacterium commonly found in soil, exhibits remarkable resistance to environmental stresses. Its spores, except for the mutant strain ATCC 7061, withstand UV light exposure, desiccation, and the presence of oxidizers like hydrogen peroxide. Strains of B. pumilus at the NASA Jet Propulsion Laboratory are particularly resistant to hydrogen peroxide. Additionally, a B. pumilus strain isolated from black tiger shrimp demonstrates high salt tolerance and inhibits the growth of marine pathogens. The cellular structure of B. pumilus resembles other Bacillus species, with peptidoglycan cross-links covered by teichoic and lipoteichoic acids. These acids aid in adhesion to different surfaces and provide a net negative charge on the cell surface, allowing the capture of essential cations like Ca2+ and Mg2+. B. pumilus strain GB34 is used in agricultural fungicides to prevent Rhizoctonia and Fusarium spores from germinating on plant roots. Additionally, B. pumilus (ATCC 27142) serves as a biological indicator for monitoring radiation sterilization processes, although its relevance has diminished due to other organisms with higher radiation resistance