Cloned (Comment) | Organism |
---|---|
expression of GST-tagged DgAS | Deinococcus geothermalis |
expression of GST-tagged DgAS | Neisseria polysaccharea |
Crystallization (Comment) | Organism |
---|---|
purified recombinant detagged DgAS, free and in complex with turanose, hanging drop vapor diffusion method, X-ray diffraction structure determination and analysis at 1.97-2.10 A resolution | Deinococcus geothermalis |
purified recombinant detagged NpAS in complex with turanose, hanging drop vapor diffusion method, 1:1 v/v ratio of protein, containing 6 mg/ml in 20 mM Tris, pH 8.0, to precipitant solution containing 1.5 M sodium acetate, 0.1 M sodium cacodylate, pH 7.0, 2 weeks, X-ray diffraction structure determination and analysis at 1.85 A resolution | Neisseria polysaccharea |
Protein Variants | Comment | Organism |
---|---|---|
E328Q | inactive mutant | Neisseria polysaccharea |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
sucrose + [(1->4)-alpha-D-glucosyl]n | Deinococcus geothermalis | - |
D-fructose + [(1->4)-alpha-D-glucosyl]n+1 | - |
? | |
sucrose + [(1->4)-alpha-D-glucosyl]n | Neisseria polysaccharea | - |
D-fructose + [(1->4)-alpha-D-glucosyl]n+1 | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Deinococcus geothermalis | - |
- |
- |
Neisseria polysaccharea | Q9ZEU2 | - |
- |
Purification (Comment) | Organism |
---|---|
recombinant GST-tagged DgAS by glutathione affinity chromatography, followed by proteolytic removal of the GST-tag | Deinococcus geothermalis |
recombinant GST-tagged NpAS by glutathione affinity chromatography, followed by proteolytic removal of the GST-tag | Neisseria polysaccharea |
Reaction | Comment | Organism | Reaction ID |
---|---|---|---|
sucrose + [(1->4)-alpha-D-glucosyl]n = D-fructose + [(1->4)-alpha-D-glucosyl]n+1 | DgAS binds the furanoid tautomers of fructose through a weak network of interactions to enable turanose formation. Such topology at subsite +1 is likely favoring other possible fructose binding modes as reported for Neisseria polysaccharea NpAS in agreement with the higher amount of trehalulose formed by DgAS. Residues Glu326 and Asp284 of DgAS are the general acid/base and the nucleophile, respectively, involved in the formation of the beta-glucosyl intermediate occurring in the alpha-retaining mechanism | Deinococcus geothermalis | |
sucrose + [(1->4)-alpha-D-glucosyl]n = D-fructose + [(1->4)-alpha-D-glucosyl]n+1 | in Neisseria polysaccharea NpAS key residues force the fructosyl moiety to bind in an open state with the O3' ideally positioned to explain the preferential formation of turanose by NpAS. Residues Glu328 and Asp286 of NpAS are the general acid/base and the nucleophile, respectively, involved in the formation of the beta-glucosyl intermediate occurring in the alpha-retaining mechanism | Neisseria polysaccharea |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
additional information | synthesis of sucrose isomers turanose and trehalulose from sucrose in the presence of fructose by DgAS, turanose binding site structure, overview | Deinococcus geothermalis | ? | - |
? | |
additional information | synthesis of sucrose isomers turanose and trehalulose from sucrose in the presence of fructose by NpAS, turanose binding site structure, overview | Neisseria polysaccharea | ? | - |
? | |
sucrose + [(1->4)-alpha-D-glucosyl]n | - |
Deinococcus geothermalis | D-fructose + [(1->4)-alpha-D-glucosyl]n+1 | - |
? | |
sucrose + [(1->4)-alpha-D-glucosyl]n | - |
Neisseria polysaccharea | D-fructose + [(1->4)-alpha-D-glucosyl]n+1 | - |
? |
Subunits | Comment | Organism |
---|---|---|
homodimer | three-dimensional structure and dimer interface analysis. The quaternary organization is likely to participate in the enhanced thermal stability of the protein. Structure comparison with the amylosucrase from Neisseria polysaccharea, overview | Deinococcus geothermalis |
More | three-dimensional structure analysis. Structure comparison with the amylosucrase from Deinococcus geothermalis, overview | Neisseria polysaccharea |
Synonyms | Comment | Organism |
---|---|---|
DGAS | - |
Deinococcus geothermalis |
NPAS | - |
Neisseria polysaccharea |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
50 | - |
sucrose isomer synthesis | Deinococcus geothermalis |
50 | - |
sucrose isomer synthesis | Neisseria polysaccharea |
Temperature Stability Minimum [°C] | Temperature Stability Maximum [°C] | Comment | Organism |
---|---|---|---|
additional information | - |
the quaternary organization is likely to participate in the enhanced thermal stability of the protein | Deinococcus geothermalis |
additional information | - |
the quaternary organization is likely to participate in the enhanced thermal stability of the protein | Neisseria polysaccharea |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7 | - |
assay at | Deinococcus geothermalis |
7 | - |
assay at | Neisseria polysaccharea |
General Information | Comment | Organism |
---|---|---|
evolution | the enzyme belongs to the glycohydrolase family 13, GH13 | Deinococcus geothermalis |
evolution | the enzyme belongs to the glycohydrolase family 13, GH13 | Neisseria polysaccharea |
additional information | the catalytic domain A of DgAS adopts the typical (alpha/alpha)8-barrel of the GH family 13 | Deinococcus geothermalis |
additional information | the catalytic domain A of NpAS adopts the typical (alpha/alpha)8-barrel of the GH family 13 | Neisseria polysaccharea |
physiological function | amylosucrases are sucrose-utilizing alpha-transglucosidases that naturally catalyze the synthesis of alpha-glucans, linked exclusively through alpha-1,4-linkages. Side products and in particular sucrose isomers such as turanose and trehalulose are also produced by these enzymes | Deinococcus geothermalis |
physiological function | amylosucrases are sucrose-utilizing alpha-transglucosidases that naturally catalyze the synthesis of alpha-glucans, linked exclusively through alpha-1,4-linkages. Side products and in particular sucrose isomers such as turanose and trehalulose are also produced by these enzymes | Neisseria polysaccharea |