Reaction: Transfers the non-reducing terminal α-D-glucose residue from a (1→4)-α-D-glucan to the 4-position of a free glucose or of a glucosyl residue at the non-reducing terminus of a (1→4)-α-D-glucan, thus bringing about the rearrangement of oligosaccharides
Other name(s): amylase III; 1,4-α-glucan:1,4-α-glucan 4-α-glucosyltransferase; 1,4-α-D-glucan:1,4-α-D-glucan 4-α-D-glucosyltransferase; α-1,4-transglucosylase
Systematic name: (1→4)-α-D-glucan:(1→4)-α-D-glucan 4-α-D-glucosyltransferase
Comments: The enzyme acts on amylose, amylopectin, glycogen and maltooligosaccharides. No detectable free glucose is formed, indicating the enzyme does not act as a hydrolase. The enzyme from the bacterium Cellvibrio japonicus has the highest activity with maltotriose as a donor, and also accepts maltose [3], while the enzyme from amoeba does not accept maltose [1,2]. Oligosaccharides with 1→6 linkages cannot function as donors, but can act as acceptors [3]. Unlike EC 2.4.1.25, 4-α-glucanotransferase, this enzyme can transfer only a single glucosyl residue.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9000-92-4
References:
1. Nebinger, P. Separation and characterization of four different amylases of Entamoeba histolytica. I. Purification and properties. Biol. Chem. Hoppe-Seyler 367 (1986) 161-167. [PMID: 2423097]
2. Nebinger, P. Separation and characterization of four different amylases of Entamoeba histolytica. II. Characterization of amylases. Biol. Chem. Hoppe-Seyler 367 (1986) 169-176. [PMID: 2423098]
3. Larsbrink, J., Izumi, A., Hemsworth, G.R., Davies, G.J. and Brumer, H. Structural enzymology of Cellvibrio japonicus Agd31B protein reveals α-transglucosylase activity in glycoside hydrolase family 31. J. Biol. Chem. 287 (2012) 43288-43299. [PMID: 23132856]