Geobacillus

Geobacillus

(jē″ō-bă-sĭl′ŭs) [Gr. ge, earth + ″] A genus of heat- and pressure-resistant motile gram-positive aerobic or facultatively anaerobic spore-forming rod-shaped bacteria. The bacteria thrive at temperatures from 35° to 75°C. The ability of this genus to survive at high temperatures is used as a biological indicator of the effectiveness of sterilizers used in medicine and dentistry.