EC Number | Cloned (Comment) | Organism |
---|---|---|
3.2.1.1 | gene ami, recombinant expression of wild-type enzyme and deletion mutant in Bacillus subtilis strain 1A751 | Geobacillus stearothermophilus |
EC Number | Protein Variants | Comment | Organism |
---|---|---|---|
3.2.1.1 | additional information | construction of a dexadletion mutant AmySDELTAR179-G180 by deleting Arg179 and Gly180 through site-directed mutagenesis. The thermostability of mutant AmySDELTAR179-G180 is enhanced and the half-life at 100°C significantly increased from 24 to 33 min. In addition, AmySDELTAR179-G180 exhibits greatxader acid resistance and lower calcium requirements to maintain alpha-amylase activity compared to the wild-type enzyme AmyS. The sexadcretory capacity of the recombinant strain is evaluated by fed-batch fermentation in a 7.5-litre fermenter in which high alpha-amylase activity is obtained. The highest activity reaches 3300 U/ml with a high productivity of 45.8 U/(ml*h). Structural comparison of the AmyS model with that of the AmySDELTAR179-G180 mutant model shows that the deletion of R179-G180 causes a slight structural rearrangement and a decrease in AmySDELTAR179-G180 calcium requirements | Geobacillus stearothermophilus |
EC Number | Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|---|
3.2.1.1 | starch + H2O | Geobacillus stearothermophilus | alpha-amylases are classical calcium-binding enzymes, which randomly hydrolyze internal alpha-1,4-glucosidic linkages in starch to produce smaller molecular mass maltodextrins, maltooligosaccharides and glucose | ? | - |
? |
EC Number | Organism | UniProt | Comment | Textmining |
---|---|---|---|---|
3.2.1.1 | Geobacillus stearothermophilus | O31193 | i.e. Bacillus stearothermophilus | - |
EC Number | Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|---|
3.2.1.1 | starch + H2O | - |
Geobacillus stearothermophilus | ? | - |
? | |
3.2.1.1 | starch + H2O | alpha-amylases are classical calcium-binding enzymes, which randomly hydrolyze internal alpha-1,4-glucosidic linkages in starch to produce smaller molecular mass maltodextrins, maltooligosaccharides and glucose | Geobacillus stearothermophilus | ? | - |
? |
EC Number | Subunits | Comment | Organism |
---|---|---|---|
3.2.1.1 | ? | x * 58000, recombinant wild-type enzyme, SDS-PAGE | Geobacillus stearothermophilus |
EC Number | Synonyms | Comment | Organism |
---|---|---|---|
3.2.1.1 | 1,4-alpha-D-glucan glucanohydrolase | - |
Geobacillus stearothermophilus |
3.2.1.1 | ami | - |
Geobacillus stearothermophilus |
3.2.1.1 | AmyS | - |
Geobacillus stearothermophilus |
EC Number | Temperature Stability Minimum [°C] | Temperature Stability Maximum [°C] | Comment | Organism |
---|---|---|---|---|
3.2.1.1 | 100 | - |
purified recombinant wild-type enzyme AmyS, half-life is 24 min, for the purified recombinant mutant AmySxadDELTAR179-G180 half-life is 33 min | Geobacillus stearothermophilus |
EC Number | General Information | Comment | Organism |
---|---|---|---|
3.2.1.1 | additional information | homology modeling of native AmyS and mutant AmySxadDELTAR179-G180 structures are created using the wild-type BStA (PDB ID 1HVX) as a template. A small extra loop containing residues Arg179-Gly180 is located in domain B of AmyS | Geobacillus stearothermophilus |
3.2.1.1 | physiological function | alpha-amylases are classical calcium-binding enzymes, which randomly hydrolyze internal alpha-1,4-glucosidic linkages in starch to produce smaller molecular mass maltodextrins, maltooligosaccharides and glucose | Geobacillus stearothermophilus |