Literature summary extracted from
Miyake, H.; Otsuka, C.; Nishimura, S.; Nitta, Y.
Catalytic mechanism of beta-amylase from Bacillus cereus var. mycoides: chemical rescue of hydrolytic activity for a catalytic site mutant (Glu367-->Ala) by azide (2002), J. Biochem., 131, 587-591.
Protein Variants
EC Number |
Protein Variants |
Comment |
Organism |
---|
3.2.1.2 |
E172A |
catalytic site mutant, no hydrolytic activity, no rescue of activity by 2 M azide |
Bacillus cereus |
3.2.1.2 |
E172A/E367A |
catalytic site double mutant, no hydrolytic activity, no rescue of activity by 2 M azide |
Bacillus cereus |
3.2.1.2 |
E367A |
catalytic site mutant, no hydrolytic activity in the absence of azide, in the presence of 2 M azide the mutant enzyme hydrolyzes maltopentaose at pH 7 and 25°C producing maltose, mechanism |
Bacillus cereus |
Organism
EC Number |
Organism |
UniProt |
Comment |
Textmining |
---|
3.2.1.2 |
Bacillus cereus |
- |
var. mycoides |
- |
Purification (Commentary)
EC Number |
Purification (Comment) |
Organism |
---|
3.2.1.2 |
E172A, E367A and E172A/E367A mutant enzymes |
Bacillus cereus |
Reaction
EC Number |
Reaction |
Comment |
Organism |
Reaction ID |
---|
3.2.1.2 |
(alpha-D-glucopyranosyl-(1-4))n-alpha-D-glucopyranose + H2O = (alpha-D-glucopyranosyl-(1-4))n-2-alpha-D-glucopyranose + alpha-D-glucopyranosyl-(1-4)-beta-D-glucopyranose |
catalytic mechanism, reaction mechanism |
Bacillus cereus |
|
Substrates and Products (Substrate)
EC Number |
Substrates |
Comment Substrates |
Organism |
Products |
Comment (Products) |
Rev. |
Reac. |
---|
3.2.1.2 |
maltopentaose + H2O |
beta-amylase is an inverting enzyme that hydrolyzes the alpha-1,4-glucosidic linkage of the substrate liberating beta-maltose from the non-reducing end, catalytic mechanism, Glu-172 acts as general acid, Glu-367 acts as general base |
Bacillus cereus |
? |
- |
? |
|
3.2.1.2 |
starch + H2O |
beta-amylase is an inverting enzyme that hydrolyzes the alpha-1,4-glucosidic linkage of the substrate liberating beta-maltose from the non-reducing end, catalytic mechanism, Glu-172 acts as general acid, Glu-367 acts as general base |
Bacillus cereus |
? |
- |
? |
|
Temperature Optimum [°C]
EC Number |
Temperature Optimum [°C] |
Temperature Optimum Maximum [°C] |
Comment |
Organism |
---|
3.2.1.2 |
25 |
- |
assay at |
Bacillus cereus |
pH Optimum
EC Number |
pH Optimum Minimum |
pH Optimum Maximum |
Comment |
Organism |
---|
3.2.1.2 |
7 |
- |
assay at |
Bacillus cereus |