Alpha amylase catalytic domain found in 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). 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.

maltodextrin glucosidase; Provisional

bifunctional glycogen debranching protein GlgX/4-alpha-glucanotransferase.

Glycosidase [Carbohydrate transport and metabolism].

Alpha amylase catalytic domain found in 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 mainly 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.

Crystalstructure of Nostoc Punctiforme Debranching Enzyme(NPDE)(Acarbose soaked) [Nostoc punctiforme],2WCS_A Crystal Structure of Debranching enzyme from Nostoc punctiforme (NPDE) [Nostoc punctiforme],2WKG_A Chain A, Alpha Amylase, Catalytic Region [Nostoc punctiforme PCC 73102]

CrystalStructure of Ttha1563 from Thermus thermophilus HB8 [Thermus thermophilus HB8],2Z1K_B Crystal Structure of Ttha1563 from Thermus thermophilus HB8 [Thermus thermophilus HB8],2Z1K_C Crystal Structure of Ttha1563 from Thermus thermophilus HB8 [Thermus thermophilus HB8],2Z1K_D Crystal Structure of Ttha1563 from Thermus thermophilus HB8 [Thermus thermophilus HB8]

ChainA, Pullulanase type II, GH13 family [Thermococcus kodakarensis]

ChainA, ALPHA AMYLASE II [Thermoactinomyces vulgaris],1JF6_B Chain B, ALPHA AMYLASE II [Thermoactinomyces vulgaris]

Alpha-amylaseIi (tvaii) From Thermoactinomyces Vulgaris R-47 [Thermoactinomyces vulgaris],1BVZ_B Alpha-amylase Ii (tvaii) From Thermoactinomyces Vulgaris R-47 [Thermoactinomyces vulgaris],1JI2_A Improved X-ray Structure of Thermoactinomyces vulgaris R-47 alpha-Amylase 2 [Thermoactinomyces vulgaris],1JI2_B Improved X-ray Structure of Thermoactinomyces vulgaris R-47 alpha-Amylase 2 [Thermoactinomyces vulgaris],3A6O_A Crystal structure of Thermoactinomyces vulgaris R-47 alpha-amylase 2/acarbose complex [Thermoactinomyces vulgaris],3A6O_B Crystal structure of Thermoactinomyces vulgaris R-47 alpha-amylase 2/acarbose complex [Thermoactinomyces vulgaris]

Amylopullulanase OS=Thermoanaerobacter pseudethanolicus (strain ATCC 33223 / 39E) OX=340099 GN=apu PE=1 SV=2

Amylopullulanase OS=Thermoanaerobacter thermohydrosulfuricus OX=1516 GN=apu PE=1 SV=1

Amylopullulanase OS=Thermoanaerobacterium saccharolyticum OX=28896 GN=apu PE=3 SV=2

Amylopullulanase OS=Thermoanaerobacterium thermosulfurigenes OX=33950 GN=amyB PE=3 SV=2

Cyclomaltodextrinase OS=Lysinibacillus sphaericus OX=1421 PE=1 SV=1