N-terminal catalytic domain of heat stable retaining glycoside hydrolase family 57
Glycoside hydrolase family 57(GH57) is a chiefly prokaryotic family with the majority of thermostable enzymes coming from extremophiles (many of these are archaeal hyperthermophiles), which exhibit the enzyme specificities of alpha-amylase (EC 3.2.1.1), 4-alpha-glucanotransferase (EC 2.4.1.25), amylopullulanase (EC 3.2.1.1/41), and alpha-galactosidase (EC 3.2.1.22). This family also includes many hypothetical proteins with uncharacterized activity and specificity. GH57s cleave alpha-glycosidic bonds by employing a retaining mechanism, which involves a glycosyl-enzyme intermediate, allowing transglycosylation.
Structure:3N98; Thermococcus kodakaraensis branching-enzyme TK1436 binds two glucose and two glycerol molecules in the substrate binding site, contacts at 4A.
Jiyao W et al.(2023). "The conserved domain database in 2023.",