Cellulose is an organic compound with the formula (C6H10O5)n. It is a structural polysaccharide derived from beta-glucose.[1][2] Cellulose is the primary structural component of green plants. The primary cell wall of green plants is made of cellulose; acetic acid bacteria are also known to synthesize cellulose, as well as many forms of algae, and the oomycetes. Cellulose was discovered and isolated in the mid-nineteenth century by the French chemist Anselme Payen[3][1] and, as of the year 2006, the estimated annual production of 1.5x109 tonnes.[4] Some animals, particularly ruminants and termites, can digest cellulose with the help of symbiotic micro-organisms (see methanogen). Cellulose is not digestible by humans and is often referred to as 'dietary fiber' or 'roughage', acting as a hydrophilic bulking agent for feces.
Breakdown (cellulolysis)
Cellulolysis is the process relating to or causing the hydrolysis of cellulose (i.e. cellulolytic bacteria, fungi or enzymes).
Mammals do not have the ability to break down cellulose directly. Typically, this ability is possessed only by certain bacteria (which have specific enzymes) like Cellulomonas etc., and which are often the flora on the gut walls of ruminants like cows and sheep, or by fungi, which in nature are responsible for cycling of nutrients. The enzymes utilized to cleave the glycosidic linkage in cellulose are glycoside hydrolases including endo-acting cellulases and exo-acting glucosidases. Such enzymes are usually secreted as part of multienzyme complexes that may include dockerins and cellulose binding modules, referred to in some cases as cellulosomes.
Many cellulolytic bacteria, fungi or enzymes break down cellulose into shorter linked chains known as cellodextrins.
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