Alternansucrase | |||||||||
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![]() Alternansucrase (dextransucrase) monomer, Leuconostoc citreum | |||||||||
Identifiers | |||||||||
EC no. | 2.4.1.140 | ||||||||
CAS no. | 100630-46-4 | ||||||||
Databases | |||||||||
IntEnz | IntEnz view | ||||||||
BRENDA | BRENDA entry | ||||||||
ExPASy | NiceZyme view | ||||||||
KEGG | KEGG entry | ||||||||
MetaCyc | metabolic pathway | ||||||||
PRIAM | profile | ||||||||
PDB structures | RCSB PDB PDBe PDBsum | ||||||||
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In enzymology, an alternansucrase (EC 2.4.1.140) is an enzyme that catalyzes a chemical reaction that transfers an alpha-D-glucosyl residue from sucrose alternately to the 6- and 3-positions of the non-reducing terminal residue of an alpha-D-glucan, thereby creating a glucan with alternating alpha-1,6- and alpha-1,3-bonds. The name "alternan" was coined in 1982 (Cote & Robyt) for the glucan based on its alternating linkage structure.
This enzyme belongs to the family of glycosyltransferases, specifically the hexosyltransferases. The systematic name of this enzyme class is sucrose:1,6(1,3)-alpha-D-glucan 6(3)-alpha-D-glucosyltransferase. Other names in common use include sucrose-1,6(3)-alpha-glucan 6(3)-alpha-glucosyltransferase, sucrose:1,6-, 1,3-alpha-D-glucan 3-alpha- and, and 6-alpha-D-glucosyltransferase.
A debranching enzyme is a molecule that helps facilitate the breakdown of glycogen, which serves as a store of glucose in the body, through glucosyltransferase and glucosidase activity. Together with phosphorylases, debranching enzymes mobilize glucose reserves from glycogen deposits in the muscles and liver. This constitutes a major source of energy reserves in most organisms. Glycogen breakdown is highly regulated in the body, especially in the liver, by various hormones including insulin and glucagon, to maintain a homeostatic balance of blood-glucose levels. When glycogen breakdown is compromised by mutations in the glycogen debranching enzyme, metabolic diseases such as Glycogen storage disease type III can result.
A glucan is a polysaccharide derived from D-glucose, linked by glycosidic bonds. Glucans are noted in two forms: alpha glucans and beta glucans. Many beta-glucans are medically important. They represent a drug target for antifungal medications of the echinocandin class.
In enzymology, a 1,4-alpha-glucan 6-alpha-glucosyltransferase is an enzyme that catalyzes the chemical reaction that transfers an alpha-D-glucosyl residue in a 1,4-alpha-D-glucan to the primary hydroxyl group of glucose or 1,4-alpha-D-glucan.
GTFC may refer to:
In enzymology, an isomaltulose synthase is an enzyme that catalyzes the chemical reaction
In enzymology, a 1,3-beta-D-glucan phosphorylase is an enzyme that catalyzes the chemical reaction
In enzymology, an alpha-1,3-glucan synthase is an enzyme that catalyzes the chemical reaction
In enzymology, an amylosucrase is an enzyme that catalyzes the chemical reaction
In enzymology, a cellulose synthase (GDP-forming) is an enzyme that catalyzes the chemical reaction
In enzymology, a dextransucrase is an enzyme that catalyzes the chemical reaction
In enzymology, a dextrin dextranase is an enzyme that catalyzes the chemical reaction
In enzymology, a 4-alpha-glucanotransferase is an enzyme that catalyzes a chemical reaction that transfers a segment of a 1,4-alpha-D-glucan to a new position in an acceptor carbohydrate, which may be glucose or a 1,4-alpha-D-glucan.
In enzymology, a starch synthase is an enzyme that catalyzes the chemical reaction
In enzymology, a sucrose-1,6-alpha-glucan 3(6)-alpha-glucosyltransferase is an enzyme that catalyzes the chemical reaction
Sucrose-phosphate synthase (SPS) is a plant enzyme involved in sucrose biosynthesis. Specifically, this enzyme catalyzes the transfer of a hexosyl group from uridine diphosphate glucose (UDP-glucose) to D-fructose 6-phosphate to form UDP and D-sucrose-6-phosphate. This reversible step acts as the key regulatory control point in sucrose biosynthesis, and is an excellent example of various key enzyme regulation strategies such as allosteric control and reversible phosphorylation.
In enzymology, an oligosaccharide 4-alpha-D-glucosyltransferase is an enzyme that catalyzes the chemical reaction in which the non-reducing terminal alpha-D-glucose residue is transferred from a 1,4-alpha-D-glucan to the 4-position of an alpha-D-glucan. This enzyme is useful in hydrolyzing oligosaccharides.
Glucansucrase is an enzyme in the glycoside hydrolase family GH70 used by lactic acid bacteria to split sucrose and use resulting glucose molecules to build long, sticky biofilm chains. These extracellular homopolysaccharides are called α-glucan polymers.
Glucanases are enzymes that break down large polysaccharides via hydrolysis. The product of the hydrolysis reaction is called a glucan, a linear polysaccharide made of up to 1200 glucose monomers, held together with glycosidic bonds. Glucans are abundant in the endosperm cell walls of cereals such as barley, rye, sorghum, rice, and wheat. Glucanases are also referred to as lichenases, hydrolases, glycosidases, glycosyl hydrolases, and/or laminarinases. Many types of glucanases share similar amino acid sequences but vastly different substrates. Of the known endo-glucanases, 1,3-1,4-β-glucanase is considered the most active.
Sucrose:1,6-, 1,3-α-D-glucan 3-α- and 6-α-D-glucosyltransferase may refer to:-
Neopullulanase is an enzyme of the alpha-amylase family with systematic name pullulan 4-D-glucanohydrolase (panose-forming). This enzyme principally catalyses the following chemical reaction by cleaving pullulan's alpha-1,4-glucosidic bonds: