Bacillus species are rod-shaped, endospore-forming aerobic or facultatively anaerobic, Gram-positive bacteria. Many of the physiologic properties and specialized metabolites of Bacillus species are used in the pharmaceutical, agricultural, and food industries. The spores of the obligate thermophile B. stearothermophilus are used to test heat sterilization procedures, and B. subtilis subsp. globigii, which is resistant to heat, chemicals, and radiation, is widely used to validate alternative sterilization and fumigation procedures.