Alpha amylase catalytic domain family; 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; and 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 this 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   1 GDGVGDLKGLTAKLDYLQWLGVDCLWLPPFFKSPLRDGGYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNH 80
Cdd:cd11334    20 GDGIGDFRGLTEKLDYLQWLGVTAIWLLPFYPSPLRDDGYDIADYYGVDPRLGTLGDFVEFLREAHERGIRVIIDLVVNH 99

                          90
                  ....*....|.
gi 2695115028  81 TSDQHPWFQES 91
Cdd:cd11334   100 TSDQHPWFQAA 110

Alpha amylase catalytic domain found in Trehalose synthetase; Trehalose synthetase (TreS) catalyzes the reversible interconversion of trehalose and maltose. The enzyme catalyzes the reaction in both directions, but the preferred substrate is maltose. Glucose is formed as a by-product of this reaction. It is believed that the catalytic mechanism may involve the cutting of the incoming disaccharide and transfer of a glucose to an enzyme-bound glucose. This enzyme also catalyzes production of a glucosamine disaccharide from maltose and glucosamine. 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   1 GDGVGDLKGLTAKLDYLQWLGVDCLWLPPFFKSPLRDGGYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNH 80
Cdd:cd11334    20 GDGIGDFRGLTEKLDYLQWLGVTAIWLLPFYPSPLRDDGYDIADYYGVDPRLGTLGDFVEFLREAHERGIRVIIDLVVNH 99

                          90
                  ....*....|.
gi 2695115028  81 TSDQHPWFQES 91
Cdd:cd11334   100 TSDQHPWFQAA 110

trehalose-6-phosphate hydrolase; Provisional

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   1 GDGVGDLKGLTAKLDYLQWLGVDCLWLPPFFKSPLRDGGYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNH 80
Cdd:PRK10933   26 GSGTGDLRGVTQRLDYLQKLGVDAIWLTPFYVSPQVDNGYDVANYTAIDPTYGTLDDFDELVAQAKSRGIRIILDMVFNH 105

                          90
                  ....*....|.
gi 2695115028  81 TSDQHPWFQES 91
Cdd:PRK10933  106 TSTQHAWFREA 116

Alpha-amylase domain;

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028    1 GDGVGDLKGLTAKLDYLQWLGVDCLWLPPFFKSPL---RDGGYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFV 77
Cdd:smart00642  12 GDGGGDLQGIIEKLDYLKDLGVTAIWLSPIFESPQgypSYHGYDISDYKQIDPRFGTMEDFKELVDAAHARGIKVILDVV 91

                   ....*.
gi 2695115028   78 MNHTSD 83
Cdd:smart00642  92 INHTSD 97

Alpha amylase catalytic domain found in Trehalose synthetase; Trehalose synthetase (TreS) catalyzes the reversible interconversion of trehalose and maltose. The enzyme catalyzes the reaction in both directions, but the preferred substrate is maltose. Glucose is formed as a by-product of this reaction. It is believed that the catalytic mechanism may involve the cutting of the incoming disaccharide and transfer of a glucose to an enzyme-bound glucose. This enzyme also catalyzes production of a glucosamine disaccharide from maltose and glucosamine. 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   1 GDGVGDLKGLTAKLDYLQWLGVDCLWLPPFFKSPLRDGGYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNH 80
Cdd:cd11334    20 GDGIGDFRGLTEKLDYLQWLGVTAIWLLPFYPSPLRDDGYDIADYYGVDPRLGTLGDFVEFLREAHERGIRVIIDLVVNH 99

                          90
                  ....*....|.
gi 2695115028  81 TSDQHPWFQES 91
Cdd:cd11334   100 TSDQHPWFQAA 110

Alpha amylase catalytic domain found in Sucrose isomerases, oligo-1,6-glucosidase (also called isomaltase; sucrase-isomaltase; alpha-limit dextrinase), dextran glucosidase (also called glucan 1,6-alpha-glucosidase), and related proteins; The sucrose isomerases (SIs) Isomaltulose synthase (EC 5.4.99.11) and Trehalose synthase (EC 5.4.99.16) catalyze the isomerization of sucrose and maltose to produce isomaltulose and trehalulose, respectively. Oligo-1,6-glucosidase (EC 3.2.1.10) hydrolyzes the alpha-1,6-glucosidic linkage of isomaltooligosaccharides, pannose, and dextran. Unlike alpha-1,4-glucosidases (EC 3.2.1.20), it fails to hydrolyze the alpha-1,4-glucosidic bonds of maltosaccharides. Dextran glucosidase (DGase, EC 3.2.1.70) hydrolyzes alpha-1,6-glucosidic linkages at the non-reducing end of panose, isomaltooligosaccharides and dextran to produce alpha-glucose.The common reaction chemistry of the alpha-amylase family enzymes is based on a two-step acid catalytic mechanism that requires two critical carboxylates: one acting as a general acid/base (Glu) and the other as a nucleophile (Asp). Both hydrolysis and transglycosylation proceed via the nucleophilic substitution reaction between the anomeric carbon, C1 and a nucleophile. Both enzymes contain the three catalytic residues (Asp, Glu and Asp) common to the alpha-amylase family as well as two histidine residues which are predicted to be critical to binding the glucose residue adjacent to the scissile bond in the substrates. 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 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   1 GDGVGDLKGLTAKLDYLQWLGVDCLWLPPFFKSPLRDGGYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNH 80
Cdd:cd11333    18 GDGIGDLPGIISKLDYLKDLGVDAIWLSPIYPSPQVDNGYDISDYRAIDPEFGTMEDFDELIKEAHKRGIKIIMDLVVNH 97

                          90
                  ....*....|.
gi 2695115028  81 TSDQHPWFQES 91
Cdd:cd11333    98 TSDEHPWFQES 108

Alpha amylase catalytic domain found in oligo-1,6-glucosidase (also called isomaltase; sucrase-isomaltase; alpha-limit dextrinase), trehalose synthase (also called maltose alpha-D-glucosyltransferase), and related proteins; Oligo-1,6-glucosidase (EC 3.2.1.10) hydrolyzes the alpha-1,6-glucosidic linkage of isomaltooligosaccharides, pannose, and dextran. Unlike alpha-1,4-glucosidases (EC 3.2.1.20), it fails to hydrolyze the alpha-1,4-glucosidic bonds of maltosaccharides. Trehalose synthase (EC 5.4.99.16) catalyzes the isomerization of maltose to produce trehalulose. 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   1 GDGVGDLKGLTAKLDYLQWLGVDCLWLPPFFKSPLRDGGYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNH 80
Cdd:cd11332    21 GDGIGDLAGIRARLPYLAALGVDAIWLSPFYPSPMADGGYDVADYRDVDPLFGTLADFDALVAAAHELGLRVIVDIVPNH 100

                          90
                  ....*....|
gi 2695115028  81 TSDQHPWFQE 90
Cdd:cd11332   101 TSDQHPWFQA 110

Alpha amylase catalytic domain found in oligo-1,6-glucosidase (also called isomaltase; sucrase-isomaltase; alpha-limit dextrinase) and related proteins; Oligo-1,6-glucosidase (EC 3.2.1.10) hydrolyzes the alpha-1,6-glucosidic linkage of isomalto-oligosaccharides, pannose, and dextran. Unlike alpha-1,4-glucosidases (EC 3.2.1.20), it fails to hydrolyze the alpha-1,4-glucosidic bonds of maltosaccharides. 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   1 GDGVGDLKGLTAKLDYLQWLGVDCLWLPPFFKSPLRDGGYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNH 80
Cdd:cd11331    21 GDGVGDLRGIISRLDYLSDLGVDAVWLSPIYPSPMADFGYDVSDYCGIDPLFGTLEDFDRLVAEAHARGLKVILDFVPNH 100

                          90
                  ....*....|.
gi 2695115028  81 TSDQHPWFQES 91
Cdd:cd11331   101 TSDQHPWFLES 111

Alpha amylase catalytic domain found in Solute Carrier family 3 member 1 proteins; SLC3A1, also called Neutral and basic amino acid transport protein rBAT or NBAT, plays a role in amino acid and cystine absorption. Mutations in the gene encoding SLC3A1 causes cystinuria, an autosomal recessive disorder characterized by the failure of proximal tubules to reabsorb filtered cystine and dibasic amino acids. 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   1 GDGVGDLKGLTAKLDYLQWLGVDCLWLPPFFKSPLRDGGYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNH 80
Cdd:cd11359    21 GDGNGDLKGIREKLDYLKYLGVKTVWLSPIYKSPMKDFGYDVSDFTDIDPMFGTMEDFERLLAAMHDRGMKLIMDFVPNH 100

                          90
                  ....*....|.
gi 2695115028  81 TSDQHPWFQES 91
Cdd:cd11359   101 TSDKHEWFQLS 111

trehalose-6-phosphate hydrolase; Provisional

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   1 GDGVGDLKGLTAKLDYLQWLGVDCLWLPPFFKSPLRDGGYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNH 80
Cdd:PRK10933   26 GSGTGDLRGVTQRLDYLQKLGVDAIWLTPFYVSPQVDNGYDVANYTAIDPTYGTLDDFDELVAQAKSRGIRIILDMVFNH 105

                          90
                  ....*....|.
gi 2695115028  81 TSDQHPWFQES 91
Cdd:PRK10933  106 TSTQHAWFREA 116

Alpha-amylase domain;

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028    1 GDGVGDLKGLTAKLDYLQWLGVDCLWLPPFFKSPL---RDGGYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFV 77
Cdd:smart00642  12 GDGGGDLQGIIEKLDYLKDLGVTAIWLSPIFESPQgypSYHGYDISDYKQIDPRFGTMEDFKELVDAAHARGIKVILDVV 91

                   ....*.
gi 2695115028   78 MNHTSD 83
Cdd:smart00642  92 INHTSD 97

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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   5 GDLKGLTAKLDYLQWLGVDCLWLPPFFKSPL--RdggYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNHTS 82
Cdd:cd11338    53 GDLQGIIEKLDYLKDLGVNAIYLNPIFEAPSnhK---YDTADYFKIDPHLGTEEDFKELVEEAHKRGIRVILDGVFNHTG 129

                  ....*..
gi 2695115028  83 DQHPWFQ 89
Cdd:cd11338   130 DDSPYFQ 136

Alpha amylase catalytic domain found in Amylosucrase; Amylosucrase is a glucosyltransferase that catalyzes the transfer of a D-glucopyranosyl moiety from sucrose onto an acceptor molecule. When the acceptor is another saccharide, only alpha-1,4 linkages are produced. Unlike most amylopolysaccharide synthases, it does not require any alpha-D-glucosyl nucleoside diphosphate substrate. In the presence of glycogen it catalyzes the transfer of a D-glucose moiety onto a glycogen branch, but in its absence, it hydrolyzes sucrose and synthesizes polymers, smaller maltosaccharides, and sucrose isoforms. 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   5 GDLKGLTAKLDYLQWLGVDCLWLPPFFKSPL--RDGGYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNHTS 82
Cdd:cd11324    83 GDLKGLAEKIPYLKELGVTYLHLMPLLKPPEgdNDGGYAVSDYREVDPRLGTMEDLRALAAELRERGISLVLDFVLNHTA 162

                  ....*
gi 2695115028  83 DQHPW 87
Cdd:cd11324   163 DEHEW 167

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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   5 GDLKGLTAKLDYLQWLGVDCLWLPPFFKSPLRDG---GYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNHT 81
Cdd:cd11340    42 GDIQGIIDHLDYLQDLGVTAIWLTPLLENDMPSYsyhGYAATDFYRIDPRFGSNEDYKELVSKAHARGMKLIMDMVPNHC 121

                  ....*...
gi 2695115028  82 SDQHPWFQ 89
Cdd:cd11340   122 GSEHWWMK 129

Alpha amylase catalytic domain found in an uncharacterized protein family; 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 (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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   2 DGVGDLKGLTAKLDYLQWLGVDCLWLPPFFKSPLRDG-GYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNH 80
Cdd:cd11350    27 TERGDFKGVIDKLDYLQDLGVNAIELMPVQEFPGNDSwGYNPRHYFALDKAYGTPEDLKRLVDECHQRGIAVILDVVYNH 106

                  ....*.
gi 2695115028  81 TSDQHP 86
Cdd:cd11350   107 AEGQSP 112

Alpha amylase catalytic domain found in maltogenic amylases, cyclodextrin glycosyltransferase, and related proteins; Enzymes such as amylases, cyclomaltodextrinase (CDase), and cyclodextrin glycosyltransferase (CGTase) degrade starch to smaller oligosaccharides by hydrolyzing the alpha-D-(1,4) linkages between glucose residues. In the case of CGTases, an additional cyclization reaction is catalyzed yielding mixtures of cyclic oligosaccharides which are referred to as alpha-, beta-, or gamma-cyclodextrins (CDs), consisting of six, seven, or eight glucose residues, respectively. CGTases are characterized depending on the major product of the cyclization reaction. Besides having similar catalytic site residues, amylases and CGTases contain carbohydrate binding domains that are distant from the active site and are implicated in attaching the enzyme to raw starch granules and in guiding the amylose chain into the active site. The maltogenic alpha-amylase from Bacillus is a five-domain structure, unlike most alpha-amylases, but similar to that of cyclodextrin glycosyltransferase. In addition to the A, B, and C domains, they have a domain D and a starch-binding domain E. Maltogenic amylase is an endo-acting amylase that has activity on cyclodextrins, terminally modified linear maltodextrins, and amylose. 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   5 GDLKGLTAKLDYLQWLGVDCLWLPPFFK---SPLRDG------GYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIID 75
Cdd:cd11320    44 GDWQGIIDKLPYLKDLGVTAIWISPPVEninSPIEGGgntgyhGYWARDFKRTNEHFGTWEDFDELVDAAHANGIKVIID 123

                  ....*...
gi 2695115028  76 FVMNHTSD 83
Cdd:cd11320   124 FVPNHSSP 131

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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   7 LKGLTAKLDYLQWLGVDCLWLPPFFKSplrDG-GYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNHTSDQH 85
Cdd:cd11337    27 LLKLEDWLPHLKELGCNALYLGPVFES---DShGYDTRDYYRIDRRLGTNEDFKALVAALHERGIRVVLDGVFNHVGRDF 103

                  ..
gi 2695115028  86 PW 87
Cdd:cd11337   104 FW 105

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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   7 LKGLTAKLDYLQWLGVDCLWLPPFFKSPLRdgGYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNHTSDQHP 86
Cdd:cd11354    30 LDRLEPWLDYAVELGCNGLLLGPVFESASH--GYDTLDHYRIDPRLGDDEDFDALIAAAHERGLRVLLDGVFNHVGRSHP 107

                  ....*
gi 2695115028  87 WFQES 91
Cdd:cd11354   108 AVAQA 112

malto-oligosyltrehalose synthase; This enzyme, formally named (1->4)-alpha-D-glucan 1-alpha-D-glucosylmutase, is the TreY enzyme of the TreYZ pathway of trehalose biosynthesis, an alternative to the OtsAB pathway. Trehalose may be incorporated into more complex compounds but is best known as compatible solute. It is one of the most effective osmoprotectants, and unlike the various betaines does not require nitrogen for its synthesis. [Energy metabolism, Biosynthesis and degradation of polysaccharides]

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028  12 AKLDYLQWLGVDCLWLPPFFKS-PLRDGGYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNH 80
Cdd:TIGR02401  20 ALLPYLKSLGVSHLYLSPILTAvPGSTHGYDVVDHSEINPELGGEEGLRRLSEAARARGLGLIVDIVPNH 89

malto-oligosyltrehalose synthase;

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2695115028   11 TAKLDYLQWLGVDCLWLPPFFKSplRDG---GYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNH 80
Cdd:PRK14507   761 EAILPYLAALGISHVYASPILKA--RPGsthGYDIVDHSQINPEIGGEEGFERFCAALKAHGLGQLLDIVPNH 831

Alpha amylase catalytic domain found in Glycosyltrehalose trehalohydrolase (also called Maltooligosyl trehalose Trehalohydrolase); Glycosyltrehalose trehalohydrolase (GTHase) was discovered as part of a coupled system for the production of trehalose from soluble starch. In the first half of the reaction, glycosyltrehalose synthase (GTSase), an intramolecular glycosyl transferase, converts the glycosidic bond between the last two glucose residues of amylose from an alpha-1,4 bond to an alpha-1,1 bond, making a non-reducing glycosyl trehaloside. In the second half of the reaction, GTHase cleaves the alpha-1,4 glycosidic bond adjacent to the trehalose moiety to release trehalose and malto-oligosaccharide. Like isoamylase and other glycosidases that recognize branched oligosaccharides, GTHase contains an N-terminal extension and does not have the conserved calcium ion present in other alpha amylase family enzymes. 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. Glycosyltrehalose Trehalohydrolase Maltooligosyltrehalose Trehalohydrolase

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2695115028   5 GDLKGLTAKLDYLQWLGVDCLWLPPFFKSPLRDG-GYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNH 80
Cdd:cd11325    52 GTFDAAIERLDYLADLGVTAIELMPVAEFPGERNwGYDGVLPFAPESSYGGPDDLKRLVDAAHRRGLAVILDVVYNH 128

Alpha amylase catalytic domain found in Alpha 1,3-glucan synthase (also called uridine diphosphoglucose-1,3-alpha-glucan glucosyltransferase and 1,3-alpha-D-glucan synthase); Alpha 1,3-glucan synthase (AGS, EC 2.4.1.183) is an enzyme that catalyzes the reversible chemical reaction of UDP-glucose and [alpha-D-glucosyl-(1-3)]n to form UDP and [alpha-D-glucosyl-(1-3)]n+1. AGS is a component of fungal cell walls. The cell wall of filamentous fungi is composed of 10-15% chitin and 10-35% alpha-1,3-glucan. AGS is triggered in fungi as a response to cell wall stress and elongates the glucan chains in cell wall synthesis. This group includes proteins from Ascomycetes and Basidomycetes. 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   5 GDLKGLTAKLDYLQWLGVDCLWL--PPFFKSPLRDGGYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNHTS 82
Cdd:cd11323    94 GDIVGLVDSLDYLQGMGIKGIYIagTPFINMPWGADGYSPLDFTLLDHHFGTIADWRAAIDEIHRRGMYVVLDNTVATMG 173

                  .
gi 2695115028  83 D 83
Cdd:cd11323   174 D 174

Alpha amylase catalytic domain found in GlgE-like proteins; GlgE is a (1,4)-a-D-glucan:phosphate a-D-maltosyltransferase, involved in a-glucan biosynthesis in bacteria. It is also an anti-tuberculosis drug target. GlgE isoform I from Streptomyces coelicolor has the same catalytic and very similar kinetic properties to GlgE from Mycobacterium tuberculosis. GlgE from Streptomyces coelicolor forms a homodimer with each subunit comprising five domains (A, B, C, N, and S) and 2 inserts. Domain A is a catalytic alpha-amylase-type domain that along with domain N, which has a beta-sandwich fold and forms the core of the dimer interface, binds cyclodextrins. Domain A, B, and the 2 inserts define a well conserved donor pocket that binds maltose. Cyclodextrins competitively inhibit the binding of maltooligosaccharides to the S. coelicolor enzyme, indicating that the hydrophobic patch overlaps with the acceptor binding site. This is not the case in M. tuberculosis GlgE because cyclodextrins do not inhibit this enzyme, despite acceptor length specificity being conserved. Domain C is hypothesized to help stabilize domain A and could be involved in substrate binding. Domain S is a helix bundle that is inserted within the N domain and it plays a role in the dimer interface and interacts directly with domain B. 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   5 GDLKGLTAKLDYLQWLGVDCLWLPP-------FFK--------------SPL----RDGGYDvsdytAVLPEFGDLADFV 59
Cdd:cd11344    20 GTFRDAEARLPRIAAMGFDVLYLPPihpigrtNRKgknnalvagpgdpgSPWaigsEEGGHD-----AIHPELGTLEDFD 94

                          90       100       110
                  ....*....|....*....|....*....|.
gi 2695115028  60 EFVDAAHQRGMRVIIDFVMNHTSDqHPWFQE 90
Cdd:cd11344    95 RLVAEARELGIEVALDIALQCSPD-HPYVKE 124

Alpha amylase catalytic domain found in sucrose phosphorylase-like proteins (also called sucrose glucosyltransferase, disaccharide glucosyltransferase, and sucrose-phosphate alpha-D glucosyltransferase); Sucrose phosphorylase is a bacterial enzyme that catalyzes the phosphorolysis of sucrose to yield glucose-1-phosphate and fructose. These enzymes do not have the conserved calcium ion present in other alpha amylase family enzymes. 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.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2695115028  29 PFFKSPlRDGGYDVSDYTAVLPEFGDLADFvefvdAAHQRGMRVIIDFVMNHTSDQHPWFQE 90
Cdd:cd11356    45 PFFPYS-SDDGFSVIDYRQVNPELGDWEDI-----EALAKDFRLMFDLVINHVSSSSPWFQQ 100

1,4-alpha-glucan branching enzyme [Carbohydrate transport and metabolism];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   1 GDGVGDLKGLTAKL-DYLQWLGVDCL-WLP----PFfksplrDG--GYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRV 72
Cdd:COG0296   159 GGRFLTYRELAERLvPYLKELGFTHIeLMPvaehPF------DGswGYQPTGYFAPTSRYGTPDDFKYFVDACHQAGIGV 232

                  ....*...
gi 2695115028  73 IIDFVMNH 80
Cdd:COG0296   233 ILDWVPNH 240

cytoplasmic alpha-amylase; Reviewed

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028  10 LTAKLDYLQWLGVDCLWLPPFFKSPL--RDGGYDVSDYTAvLPEF----------GDLADFVEFVDAAHQRGMRVIIDFV 77
Cdd:PRK09441   24 LAERAPELAEAGITAVWLPPAYKGTSggYDVGYGVYDLFD-LGEFdqkgtvrtkyGTKEELLNAIDALHENGIKVYADVV 102

                  ...
gi 2695115028  78 MNH 80
Cdd:PRK09441  103 LNH 105

Alpha amylase catalytic domain family found in maltase; Maltase (EC 3.2.1.20) hydrolyzes the terminal, non-reducing (1->4)-linked alpha-D-glucose residues in maltose, releasing alpha-D-glucose. The catalytic triad (DED) which is highly conserved in the other maltase group is not present in this subfamily. 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.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*...
gi 2695115028  44 DYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNHTSDQHPWFQES 91
Cdd:cd11329   103 DETYLNNSYGVESDLKELVKTAKQKDIKVILDLTPNHSSKQHPLFKDS 150

Alpha amylase catalytic domain found in glycogen debranching enzymes; Debranching enzymes facilitate the breakdown of glycogen through glucosyltransferase and glucosidase activity. These activities are performed by a single enzyme in mammals, yeast, and some bacteria, but by two distinct enzymes in Escherichia coli and other bacteria. Debranching enzymes perform two activities: 4-alpha-D-glucanotransferase (EC 2.4.1.25) and amylo-1,6-glucosidase (EC 3.2.1.33). 4-alpha-D-glucanotransferase catalyzes the endohydrolysis of 1,6-alpha-D-glucoside linkages at points of branching in chains of 1,4-linked alpha-D-glucose residues. Amylo-alpha-1,6-glucosidase catalyzes the endohydrolysis of 1,6-alpha-D-glucoside linkages at points of branching in chains of 1,4-linked alpha-D-glucose residues. In Escherichia coli, GlgX is the debranching enzyme and malQ is the 4-alpha-glucanotransferase. TreX, an archaeal glycogen-debranching enzyme has dual activities like mammals and yeast, but is structurally similar to GlgX. TreX exists in two oligomeric states, a dimer and tetramer. Isoamylase (EC 3.2.1.68) is one of the starch-debranching enzymes that catalyzes the hydrolysis of alpha-1,6-glucosidic linkages specific in alpha-glucans such as amylopectin or glycogen and their beta-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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028  12 AKLDYLQWLGVDCLWLPPFF-----KSPLRDG-----GYDVSDYTAVLPEF-------GDLADFVEFVDAAHQRGMRVII 74
Cdd:cd11326    48 AKIPYLKELGVTAVELLPVHafddeEHLVERGltnywGYNTLNFFAPDPRYasddapgGPVDEFKAMVKALHKAGIEVIL 127

                  ....*..
gi 2695115028  75 DFVMNHT 81
Cdd:cd11326   128 DVVYNHT 134

1,4-alpha-glucan branching protein GlgB;

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2695115028  15 DYLQWLGVDCLWLPPFFKSPLrDG--GYDVSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFVMNH-TSDQH 85
Cdd:PRK12313  178 PYVKEMGYTHVEFMPLMEHPL-DGswGYQLTGYFAPTSRYGTPEDFMYLVDALHQNGIGVILDWVPGHfPKDDD 250

Alpha amylase catalytic domain found in maltosyltransferase; Maltosyltransferase (MTase), a maltodextrin glycosyltransferase, acts on starch and maltooligosaccharides. It catalyzes the transfer of maltosyl units from alpha-1,4-linked glucans or maltooligosaccharides to other alpha-1,4-linked glucans, maltooligosaccharides or glucose. MTase is a homodimer. The catalytic core domain has the (beta/alpha) 8 barrel fold with the active-site cleft formed at the C-terminal end of the barrel. Substrate binding experiments have led to the location of two distinct maltose-binding sites: one lies in the active-site cleft and the other is located in a pocket adjacent to the active-site cleft. It is a member of the alpha-amylase family, but unlike typical alpha-amylases, MTase does not require calcium for activity and lacks two histidine residues which are predicted to be critical for binding the glucose residue adjacent to the scissile bond in the substrates. The common reaction chemistry of the alpha-amylase family of enzymes is based on a two-step acid catalytic mechanism that requires two critical carboxylates: one acting as a general acid/base (Glu) and the other as a nucleophile (Asp). Both hydrolysis and transglycosylation proceed via the nucleophilic substitution reaction between the anomeric carbon, C1 and a nucleophile. 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028  12 AKLDYLQWLGVDCLWLPPFFK-----------SPlrdggYDVSDYTAVLPEFGD--LADF-VE-----FVDAAHQRGMRV 72
Cdd:cd11335    86 ALLPYLKRMGINTIYLLPITKiskkfkkgelgSP-----YAVKNFFEIDPLLHDplLGDLsVEeefkaFVEACHMLGIRV 160

                          90       100
                  ....*....|....*....|...
gi 2695115028  73 IIDFV---MNHTSD---QHP-WF 88
Cdd:cd11335   161 VLDFIprtAARDSDlilEHPeWF 183

Alpha amylase catalytic domain family found in plant isoamylases; Two types of debranching enzymes exist in plants: isoamylase-type (EC 3.2.1.68) and a pullulanase-type (EC 3.2.1.41, also known as limit-dextrinase). These efficiently hydrolyze alpha-(1,6)-linkages in amylopectin and pullulan. This group does not contain the conserved catalytic triad present in other alpha-amylase-like proteins. 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   5 GDLKGLTAKLDYLQWLGVDCLWLPPFFKSPLRDGGYD-------VSDYTAVLPEFGDLADFVEFVDAAHQRGMRVIIDFV 77
Cdd:cd11346    29 GTFLGVLEKVDHLKSLGVNTVLLQPIFAFARVKGPYYppsffsaPDPYGAGDSSLSASAELRAMVKGLHSNGIEVLLEVV 108

                  ....*.
gi 2695115028  78 MNHTSD 83
Cdd:cd11346   109 LTHTAE 114

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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2695115028   9 GLTAKLDYLQWLGVDCLWLPPFF---------KSPLRDGGYDVSDYTAvlPEfGDLA-----------DFVEFVDAAHQR 68
Cdd:TIGR02104 165 GVSTGLDYLKELGVTHVQLLPVFdfagvdeedPNNAYNWGYDPLNYNV--PE-GSYStnpydpatrirELKQMIQALHEN 241