Cellodextrins are glucose

Glucose

Glucose is a simple sugar and an important carbohydrate in biology. Cells use it as the primary source of energy and a metabolic intermediate...

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

Cellulose

Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to over ten thousand β linked D-glucose units....

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Classification

A cellodextrin is classified by its degree of polymerization

Degree of polymerization

The degree of polymerization, or DP, is usually defined as the number of monomeric units in a macromolecule or polymer or oligomer molecule.For a homopolymer, there is only one type of monomeric unit andthe number-average degree of polymerization is given by...

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

Glycosidic bond

In chemistry, a glycosidic bond is a type of covalent bond that joins a carbohydrate molecule to another group, which may or may not be another carbohydrate....

. The most common cellodextrins are listed below:

• cellobiose
  Cellobiose
  Cellobiose is a disaccharide with the formula [HOCH2CHO3]2O. Cellobiose consists of two glucose molecules linked by a β bond. It can be hydrolyzed to glucose enzymatically or with acid. Cellobiose has eight free alcohol groups, one acetal linkage and one hemiacetal linkages, which give rise to...
  
   (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

Enzyme

Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...

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

Cleave

Cleave may refer to:*Cleave , a controlled break in optical fiber*RAF Cleave, airbase in Cornwall, England, 1939-1945-People with surname Cleave:*Chris Cleave , British journalist*Egbert Cleave , American author...

 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

Glucoside

A glucoside is a glycoside that is derived from glucose. Glucosides are common in plants, but rare in animals. Glucose is produced when a glucoside is hydrolysed by purely chemical means, or decomposed by fermentation or enzymes....

 bonds as well as the anaerobic glycolysis

Glycolysis

Glycolysis is the metabolic pathway that converts glucose C6H12O6, into pyruvate, CH3COCOO− + H+...

 of the glucose monomers. Transport of cellodextrins across the cell membrane

Cell membrane

The cell membrane or plasma membrane is a biological membrane that separates the interior of all cells from the outside environment. The cell membrane is selectively permeable to ions and organic molecules and controls the movement of substances in and out of cells. It basically protects the cell...

 is usually an active process, requiring ATP

Adenosine triphosphate

Adenosine-5'-triphosphate is a multifunctional nucleoside triphosphate used in cells as a coenzyme. It is often called the "molecular unit of currency" of intracellular energy transfer. ATP transports chemical energy within cells for metabolism...

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