Starch phosphorylase is a form of phosphorylase

Phosphorylase

Phosphorylases are enzymes that catalyze the addition of a phosphate group from an inorganic phosphate to an acceptor.They include allosteric enzymes that catalyze the production of glucose-1-phosphate from a glucan such as glycogen, starch or maltodextrin. Phosphorylase is also a common name used...

 similar to glycogen phosphorylase

Glycogen phosphorylase

Glycogen phosphorylase is one of the phosphorylase enzymes . Glycogen phosphorylase catalyzes the rate-limiting step in the degradation of glycogen in animals by releasing glucose-1-phosphate from the terminal alpha-1,4-glycosidic bond...

, except that it acts upon starch

Starch

Starch or amylum is a carbohydrate consisting of a large number of glucose units joined together by glycosidic bonds. This polysaccharide is produced by all green plants as an energy store...

 instead of glycogen

Glycogen

Glycogen is a molecule that serves as the secondary long-term energy storage in animal and fungal cells, with the primary energy stores being held in adipose tissue...

.

The plant alpha-glucan phosphorylase, commonly called starch phosphorylase (EC 2.4.1.1), is largely known for the phosphorolytic degradation of starch. Starch phosphorylase catalyzes the reversible transfer of glucosyl units from glucose-1-phosphate to the nonreducing end of alpha-1,4-D-glucan chains with the release of phosphate. Two distinct forms of starch phosphorylase, plastidic phosphorylase and cytosolic phosphorylase, have been consistently observed in higher plants.

External links

• http://www.genome.ad.jp/dbget-bin/www_bget?ko+K00688
  • Rathore RS, Garg N, Garg S, Kumar A.

Crit Rev Biotechnol. 2009;29(3):214-24.
Starch phosphorylase: role in starch metabolism and biotechnological applications.
http://informahealthcare.com/doi/abs/10.1080/07388550902926063