General Information: A non-ruminal mesophilic cellulolytic bacterium originally isolated from decayed grass compost. This genus comprises about 150 metabolically diverse species of anaerobes that are ubiquitous in virtually all anoxic habitats where organic compounds are present, including soils, aquatic sediments and the intestinal tracts of animals and humans. This shape is attributed to the presence of endospores that develop under conditions unfavorable for vegetative growth and distend single cells terminally or sub-terminally. Spores germinate under conditions favorable for vegetative growth, such as anaerobiosis and presence of organic substrates. It is believed that present day Mollicutes (Eubacteria) have evolved regressively (i.e., by genome reduction) from gram-positive clostridia-like ancestors with a low GC content in DNA. Clostridium cellulolyticum is a mesophilic cellulolytic bacterium. Cellulose-degradation by C. cellulolyticum has been extensively studied. The cellulolytic enzymes of this organism are bound to a protein scaffold in an extracellular multienzyme complex called a cellulosome.