Cellodextrins are

glucose Glucose is a sugar with the Chemical formula#Molecular formula, molecular formula , which is often abbreviated as Glc. It is overall the most abundant monosaccharide, a subcategory of carbohydrates. It is mainly made by plants and most algae d ...

polymers (

polysaccharide Polysaccharides (), or polycarbohydrates, are the most abundant carbohydrates found in food. They are long-chain polymeric carbohydrates composed of monosaccharide units bound together by glycosidic linkages. This carbohydrate can react with wat ...

s) of varying length (two or more glucose monomers) resulting from cellulolysis, the breakdown of

cellulose Cellulose is an organic compound with the chemical formula, formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of glycosidic bond, β(1→4) linked glucose, D-glucose units. Cellulose is an important s ...

Classification

A cellodextrin is classified by its

degree of polymerization The degree of polymerization, or DP, is the number of structural unit, monomeric units in a macromolecule or polymer or oligomer molecule. For a homopolymer, there is only one type of monomeric unit and the ''number-average'' degree of polymeriza ...

(DP) which indicates the number of linked glucose monomers it contains. Each glucose monomer is linked via a ''beta''-1,4

glycosidic bond A glycosidic bond or glycosidic linkage is a type of ether bond that joins a carbohydrate (sugar) molecule to another group, which may or may not be another carbohydrate. A glycosidic bond is formed between the hemiacetal or hemiketal group o ...

. The most common cellodextrins are listed below: *

cellobiose Cellobiose is a disaccharide with the formula (C6H7(OH)4O)2O. It is classified as a reducing sugar - any sugar that possesses the ability or function of a reducing agent. The chemical structure of cellobiose is derived from the condensation of a ...

(DP=2) (sometimes not included in cellodextrin classification) * cellotriose (DP=3) * cellotetraose (DP=4) * cellopentaose (DP=5) * cellohexaose (DP=6)

Function

Cellodextrins are created through the cleavage of cellulose in most anaerobic bacteria by the cellulosome (an amalgamation of cellulolytic

enzyme An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...

s on the outside of a cell). An endoglucanase first cuts the crystalline cellulose in an amorphous zone and exoglucanases subsequently

cleave Cleave may refer to: * Cleave (surname) * Cleave (fiber), a controlled break in optical fiber * RAF Cleave, was an airfield in the north of Cornwall, England, May 1939 - Nov 1945 *The process of protein cleaving as a form of post-translational mod ...

these large insoluble chunks of cellulose into smaller, soluble cellodextrins which can be used by the cell. Many cellulolytic bacteria use cellodextrins as their primary source of energy. The energy is obtained through the phosphorolytic cleavage of

glycosidic A glycosidic bond or glycosidic linkage is a type of ether bond that joins a carbohydrate (sugar) molecule to another group, which may or may not be another carbohydrate. A glycosidic bond is formed between the hemiacetal or hemiketal group of a ...

bonds as well as the anaerobic

glycolysis Glycolysis is the metabolic pathway that converts glucose () into pyruvic acid, pyruvate and, in most organisms, occurs in the liquid part of cells (the cytosol). The Thermodynamic free energy, free energy released in this process is used to form ...

of the glucose monomers. Transport of cellodextrins across the

cell membrane The cell membrane (also known as the plasma membrane or cytoplasmic membrane, and historically referred to as the plasmalemma) is a biological membrane that separates and protects the interior of a cell from the outside environment (the extr ...

is usually an active process, requiring ATP.

References

{{Reflist Polysaccharides Cellulose

Classification

Function

See also

References