Clostridia are another group of common endospore formers besides Bacillus. Unlike Bacillus, Clostridia are anaerobic, meaning they will not grow in the presence of oxygen and even the presence of oxygen will kill the vegetative cells. Their spores, however,  can survive long periods of exposure to oxygen. Some Clostridium species are pathogenic (e.g., Clostridium botulinum, Clostridium perfringens), which are very important in food industry and waste water treatment. We are developing a technique to detect anaerobic spores and distinguish them from aerobic ones. This technique will be applied to detect anaerobic spores in waste water to evaluate the treatment efficiency. We will also apply this technique to ice core and permafrost samples to study potential life in extreme environments.