alpha-1,6-glucosidases, pullulanase-type. Members of this protein family include secreted (or membrane-anchored) pullulanases of Gram-negative bacteria and pullulanase-type starch debranching enzymes of plants. Both enzymes hydrolyze alpha-1,6 glycosidic linkages. Pullulan is an unusual, industrially important polysaccharide in which short alpha-1,4 chains (maltotriose) are connected in alpha-1,6 linkages. Enzymes that cleave alpha-1,6 linkages in pullulan and release maltotriose are called pullulanases although pullulan itself may not be the natural substrate. This family is closely homologous to, but architecturally different from, the Gram-positive pullulanases of Gram-positive bacteria (TIGR02102). [Energy metabolism, Biosynthesis and degradation of polysaccharides]

alpha-amylase/limit dextrinase

Alpha amylase catalytic domain found in Pullulanase (also called dextrinase; alpha-dextrin endo-1,6-alpha glucosidase), limit dextrinase, and related proteins. Pullulanase is an enzyme with action similar to that of isoamylase; it cleaves 1,6-alpha-glucosidic linkages in pullulan, amylopectin, and glycogen, and in alpha-and beta-amylase limit-dextrins of amylopectin and glycogen. Pullulanases are very similar to limit dextrinases, although they differ in their action on glycogen and the rate of hydrolysis of limit dextrins. The Alpha-amylase family comprises the largest family of glycoside hydrolases (GH), with the majority of enzymes acting on starch, glycogen, and related oligo- and polysaccharides. These proteins catalyze the transformation of alpha-1,4 and alpha-1,6 glucosidic linkages with retention of the anomeric center. The protein is described as having 3 domains: A, B, C. A is a (beta/alpha) 8-barrel; B is a loop between the beta 3 strand and alpha 3 helix of A; C is the C-terminal extension characterized by a Greek key. The majority of the enzymes have an active site cleft found between domains A and B where a triad of catalytic residues (Asp, Glu and Asp) performs catalysis. Other members of this family have lost the catalytic activity as in the case of the human 4F2hc, or only have 2 residues that serve as the catalytic nucleophile and the acid/base, such as Thermus A4 beta-galactosidase with 2 Glu residues (GH42) and human alpha-galactosidase with 2 Asp residues (GH31). The family members are quite extensive and include: alpha amylase, maltosyltransferase, cyclodextrin glycotransferase, maltogenic amylase, neopullulanase, isoamylase, 1,4-alpha-D-glucan maltotetrahydrolase, 4-alpha-glucotransferase, oligo-1,6-glucosidase, amylosucrase, sucrose phosphorylase, and amylomaltase.

Alpha amylase catalytic domain found in bacterial cyclomaltodextrinases and related proteins. Cyclomaltodextrinase (CDase; EC3.2.1.54), neopullulanase (NPase; EC 3.2.1.135), and maltogenic amylase (MA; EC 3.2.1.133) catalyze the hydrolysis of alpha-(1,4) glycosidic linkages on a number of substrates including cyclomaltodextrins (CDs), pullulan, and starch. These enzymes hydrolyze CDs and starch to maltose and pullulan to panose by cleavage of alpha-1,4 glycosidic bonds whereas alpha-amylases essentially lack activity on CDs and pullulan. They also catalyze transglycosylation of oligosaccharides to the C3-, C4- or C6-hydroxyl groups of various acceptor sugar molecules. Since these proteins are nearly indistinguishable from each other, they are referred to as cyclomaltodextrinases (CMDs). This group of CMDs is bacterial. The Alpha-amylase family comprises the largest family of glycoside hydrolases (GH), with the majority of enzymes acting on starch, glycogen, and related oligo- and polysaccharides. These proteins catalyze the transformation of alpha-1,4 and alpha-1,6 glucosidic linkages with retention of the anomeric center. The protein is described as having 3 domains: A, B, C. A is a (beta/alpha) 8-barrel; B is a loop between the beta 3 strand and alpha 3 helix of A; C is the C-terminal extension characterized by a Greek key. The majority of the enzymes have an active site cleft found between domains A and B where a triad of catalytic residues (Asp, Glu and Asp) performs catalysis. Other members of this family have lost the catalytic activity as in the case of the human 4F2hc, or only have 2 residues that serve as the catalytic nucleophile and the acid/base, such as Thermus A4 beta-galactosidase with 2 Glu residues (GH42) and human alpha-galactosidase with 2 Asp residues (GH31). The family members are quite extensive and include: alpha amylase, maltosyltransferase, cyclodextrin glycotransferase, maltogenic amylase, neopullulanase, isoamylase, 1,4-alpha-D-glucan maltotetrahydrolase, 4-alpha-glucotransferase, oligo-1,6-glucosidase, amylosucrase, sucrose phosphorylase, and amylomaltase.

pullulanase, type I. Pullulan is an unusual, industrially important polysaccharide in which short alpha-1,4 chains (maltotriose) are connected in alpha-1,6 linkages. Enzymes that cleave alpha-1,6 linkages in pullulan and release maltotriose are called pullulanases although pullulan itself may not be the natural substrate. This family consists of pullulanases related to the subfamilies described in TIGR02102 and TIGR02103 but having a different domain architecture with shorter sequences. Members are called type I pullulanases.

BarleyLimit Dextrinase In Complex With Beta-Cyclodextrin [Hordeum vulgare],2Y5E_A BARLEY LIMIT DEXTRINASE IN COMPLEX WITH ALPHA-CYCLODEXTRIN [Hordeum vulgare],4AIO_A Crystal structure of the starch debranching enzyme barley limit dextrinase [Hordeum vulgare],4CVW_A Structure of the barley limit dextrinase-limit dextrinase inhibitor complex [Hordeum vulgare],4CVW_B Structure of the barley limit dextrinase-limit dextrinase inhibitor complex [Hordeum vulgare]

Crystalstructure of barley limit dextrinase soaked with 300mM maltotetraose [Hordeum vulgare],4J3T_A Crystal structure of barley Limit dextrinase co-crystallized with 25mM maltotetraose [Hordeum vulgare],4J3U_A Crystal structure of barley limit dextrinase in complex with maltosyl-S-betacyclodextrin [Hordeum vulgare],4J3U_B Crystal structure of barley limit dextrinase in complex with maltosyl-S-betacyclodextrin [Hordeum vulgare],4J3V_A Crystal structure of barley limit dextrinase in complex with a branched thio-linked hexasaccharide [Hordeum vulgare]

Crystalstructure of barley limit dextrinase (E510A mutant) in complex with a branched maltohexasaccharide [Hordeum vulgare],4J3X_A Crystal structure of barley limit dextrinase (E510A mutant) in complex with a branched maltoheptasaccharide [Hordeum vulgare]

ChainA, pullulanase [Klebsiella pneumoniae],6J33_B Chain B, pullulanase [Klebsiella pneumoniae],6J34_A Chain A, Pullulanase [Klebsiella pneumoniae]

ChainA, Pullulanase [Klebsiella pneumoniae],6J35_B Chain B, Pullulanase [Klebsiella pneumoniae],6J4H_A Chain A, Pullulanase [Klebsiella pneumoniae]

Pullulanase 1, chloroplastic OS=Arabidopsis thaliana OX=3702 GN=PU1 PE=1 SV=2

Alpha-amylase OS=Streptomyces lividans OX=1916 GN=amy PE=1 SV=1

Pullulanase OS=Klebsiella pneumoniae OX=573 GN=pulA PE=1 SV=2

Pullulanase OS=Klebsiella aerogenes OX=548 GN=pulA PE=1 SV=1

Pullulanase OS=Thermotoga maritima (strain ATCC 43589 / DSM 3109 / JCM 10099 / NBRC 100826 / MSB8) OX=243274 GN=pulA PE=1 SV=2