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Information on EC 3.2.1.2 - beta-amylase
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3.2.1.2 beta-amylaseIUBMB Comments
Acts on starch, glycogen and related polysaccharides and oligosaccharides producing beta-maltose by an inversion. The term 'beta'' relates to the initial anomeric configuration of the free sugar group released and not to the configuration of the linkage hydrolysed.
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Word Map
- 3.2.1.2
- starch
- alpha-amylase
- barley
- maltose
- soybean
- potato
-
sweet
- amylopectin
- hordeum
- endosperm
- amylases
-
amylolytic
- glucoamylase
- pullulanase
- dextrin
-
debranching
- amyloglucosidase
- polymyxa
- maltotetraose
-
starch-degrading
- nutrition
-
beta-limit
- isoamylase
- thermosulfurogenes
- maltotriose
- industry
-
sporamin
-
granule-bound
- brewing
- maltopentaose
- alpha-cyclodextrin
- molecular biology
-
extrachloroplastic
The expected taxonomic range for this enzyme is: Eukaryota, Bacteria, Archaea
Reaction Schemes
Synonyms
beta-amylase, arath, spoii, tr-bamy, beta amylase, ct-bmy, bam-2, beta-amylase 1, bam-8, glycogenase, 
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SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
1,4-alpha-D-glucan maltohydrolase
alpha-1,4-glucan maltohydrolase
BAM1
BAM3
beta amylase
beta-amylase
BMY
Bmy1
SBA
Sd1
Sd2H
Sd2L
TCMA
additional information
additional information
-
BAM-4 is chloroplastic, expressed in Escherichia coli with no beta-amylase activity, probably lost its catalytic capacity during evolution
additional information
member of family 14 of the sequence-based classification of glycoside hydrolases
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REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
mechanism
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
multichain type mechanism
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
catalytic mechanism
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
catalytic mechanism
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
acts on starch, glycogen and related polysaccharides and oligosaccharides producing beta-maltose by an inversion, the term beta relates to the initial anomeric configuration of the free sugar group released and not to the configuration of the linkage hydrolysed
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
catalytic mechanism, reaction mechanism
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
active site structure, carbohydrate binding subsites, role of a conformational change of the inner loop in the catalytic mechanism, T342 is involved, overview
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
general acid-base catalytic reaction mechanism
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
Glu367 is important in catalysis, the plant enzyme shows a reaction mechanism different from the bacterial enzyme, overview
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
mode of action of the exo-amylase
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
mode of action of the exo-amylase
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
mode of action of the exo-amylase
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
mode of action of the exo-amylase
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
mode of action of the exo-amylase
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
mode of action of the exo-amylase
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
mode of action of the exo-amylase
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
mode of action of the exo-amylase
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
mode of action of the exo-amylase
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
mode of action of the exo-amylase
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
mode of action of the exo-amylase
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
mode of action of the exo-amylase
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
mode of action of the exo-amylase
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
mode of action of the exo-amylase
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
roles of Glu186 and Glu380 as general acid and general base catalyst in the catalytic reaction, reaction mechanism involving residue T342
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
roles of Glu186 and Glu380 as general acid and general base catalyst in the catalytic reaction, substrate binding and reaction mechanism
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
acts on starch, glycogen and related polysaccharides and oligosaccharides producing beta-maltose by an inversion, the term beta relates to the initial anomeric configuration of the free sugar group released and not to the configuration of the linkage hydrolysed
Phaffia rhodozyma CECT 1690
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
mode of action of the exo-amylase
-
Hydrolysis of (1->4)-alpha-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
-
-
-
-
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REACTION TYPE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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PATHWAY SOURCE
PATHWAYS
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SYSTEMATIC NAME
IUBMB Comments
4-alpha-D-glucan maltohydrolase
Acts on starch, glycogen and related polysaccharides and oligosaccharides producing beta-maltose by an inversion. The term 'beta'' relates to the initial anomeric configuration of the free sugar group released and not to the configuration of the linkage hydrolysed.
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CAS REGISTRY NUMBER
COMMENTARY
9000-91-3
-
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SUBSTRATE
PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate)
(Substrate)
LITERATURE
(Substrate)
(Substrate)
COMMENTARY
(Product)
(Product)
LITERATURE
(Product)
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
4-nitrophenyl alpha-D-galactoside + H2O
4-nitrophenol + D-galactose
-
-
?
4-nitrophenyl alpha-maltopyranoside + H2O
4-nitrophenol + alpha-maltopyranose
-
-
?
4-nitrophenyl maltopentaose + H2O
4-nitrophenol + maltopentaose
-
-
?
maltodextrin + H2O
maltose
-
maltodextrins with chain length from 9 to 198 glucose residues
and very small amounts of glucose and maltotriose
?
maltoheptaose + H2O
maltose + D-glucose
the exo-type enzyme can catalyze the successive liberation of beta-maltose from the nonreducing ends of alpha-1,4-linked glucopyranosyl polymers. A phenomenon called multiple or repetitive attack is observed where the enzyme releases several maltose molecules in a single enzyme-substrate complex. The multiple attack action needs the force of enzyme sliding on the substrate. In addition, it is important for the multiple attack that the enzyme and substrate have the characteristics of a stable productive substrate-enzyme complex through a hydrogen bond between the nonreducing end of the substrate and the carboxyl residue of the enzyme
-
?
maltooligosaccharide + H2O
?
-
beta-amylase hydrolyzes maltooligosaccharides more readily as their degree of polymerization increases, this being strongest for maltooligosaccharides larger than 13 glucose residues and very weakly for maltotriose, exo-hydrolase that releases beta-maltose from the non-reducing end of alpha-1,4-linked poly- and oligoglucans until the first alpha-1,6-branching point along the substrate molecule is encountered
-
?
maltopentaose + H2O
2 maltose + D-glucose
the enzyme displays dual hydrolysis activity toward alpha-1,4- and alpha-1,6-glycosidic linkages, the catalytic efficiency of 6-O-maltosyl-beta-cyclodextrin is 16fold higher than that of maltotriose. Compared to the kcat/Km value toward maltotriose, the values for longer substrates such as maltotetraose and maltopentaose are negligible
-
?
maltopentaose + H2O
maltose
substrate/product binding structure, sugar subsite conformations, overview
-
?
maltose + H2O
?
the enzyme is specific for short alpha-glucans. Similar responses to maltose, glycogen, and starch but not to pullulan
-
?
p-nitrophenyl alpha-D-glucopyranoside + H2O
p-nitrophenol + D-glucose
-
-
-
?
p-nitrophenylmaltopentaoside + H2O
p-nitrophenol + maltopentaose
catalyzes the release of p-nitrophenol, specific substrate
-
?
soluble starch + H2O
maltose
maximum activity with 1.2 % soluble starch. Less activity is observed with starch from corn, rice, glycogen
-
?
amylopectin + H2O
?
from potato, active site structure, Glu-186 and Glu-380 play important roles as general acid and base catalyst
-
?
amylopectin + H2O
?
-
114.6% of the activity with amylose, soluble starch, amylose and amylopectin are the most suitable substrates, exo-hydrolase that releases beta-maltose from the non-reducing end of alpha-1,4-linked poly- and oligoglucans until the first alpha-1,6-branching point along the substrate molecule is encountered
-
?
amylopectin + H2O
maltose + ?
catalyzes the release of maltose residues, amylopectin and starch are better substrates than amylose
-
?
amylopectin + H2O
maltose + ?
the enzyme only releases maltose from polymers such as soluble starch, amylopectin, and glycogen, while maltose is rarely detected from reaction with amylose and pullulan
-
?
amylopectin + H2O
maltose + ?
the enzyme only releases maltose from polymers such as soluble starch, amylopectin, and glycogen, while maltose is rarely detected from reaction with amylose and pullulan
-
?
amylose + H2O
?
-
EX-I, soluble starch, amylose and amylopectin are the most suitable substrates, exo-hydrolase that releases beta-maltose from the non-reducing end of alpha-1,4-linked poly- and oligoglucans until the first alpha-1,6-branching point along the substrate molecule is encountered
-
?
amylose + H2O
maltose + ?
catalyzes the release of maltose residues, less good substrate than starch and amylopectin
-
?
glycogen + H2O
?
the enzyme is specific for short alpha-glucans. Similar responses to maltose, glycogen, and starch but not to pullulan
-
?
glycogen + H2O
maltose + ?
the enzyme only releases maltose from polymers such as soluble starch, amylopectin, and glycogen, while maltose is rarely detected from reaction with amylose and pullulan
-
?
glycogen + H2O
maltose + ?
the enzyme only releases maltose from polymers such as soluble starch, amylopectin, and glycogen, while maltose is rarely detected from reaction with amylose and pullulan
-
?
maltopentaose + H2O
?
beta-amylase is an exo-enzyme that catalyzes the hydrolysis of the alpha-1,4-glucosidic linkage of the substrate liberating beta-maltose from the non-reducing end, Glu-172 and Glu-367 are catalytic residues, binding mode of substrate, substrate recognition mechanism, enzyme structure
-
?
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
-
?
maltopentaose + H2O
?
binding mode of substrate in the active site
-
?
maltopentaose + H2O
?
hydrolyzes the alpha-1,4-glucosidic linkage liberating beta-maltose from the non-reducing end of substrate, good substrate, mode of binding in the active site, catalytic mechanism, enzyme/domain structure
-
?
maltopentose + H2O
?
-
40% of the activity with starch, exo-acting enzyme, no production of glucose
-
?
maltopentose + H2O
?
Phaffia rhodozyma CECT 1690
-
40% of the activity with starch, exo-acting enzyme, no production of glucose
-
?
maltotetraose + H2O
2 maltose
the enzyme displays dual hydrolysis activity toward alpha-1,4- and alpha-1,6-glycosidic linkages, the catalytic efficiency of 6-O-maltosyl-beta-cyclodextrin is 16fold higher than that of maltotriose. Compared to the kcat/Km value toward maltotriose, the values for longer substrates such as maltotetraose and maltopentaose are negligible
-
?
maltotetraose + H2O
2 maltose
the enzyme displays dual hydrolysis activity toward alpha-1,4- and alpha-1,6-glycosidic linkages, the catalytic efficiency of 6-O-maltosyl-beta-cyclodextrin is 16fold higher than that of maltotriose. Compared to the kcat/Km value toward maltotriose, the values for longer substrates such as maltotetraose and maltopentaose are negligible
-
?
maltotetraose + H2O
?
-
37% of the activity with starch, exo-acting enzyme, no production of glucose
-
?
maltotetraose + H2O
?
Phaffia rhodozyma CECT 1690
-
37% of the activity with starch, exo-acting enzyme, no production of glucose
-
?
maltotriose + H2O
maltose + D-glucose
the enzyme displays dual hydrolysis activity toward alpha-1,4- and alpha-1,6-glycosidic linkages, the catalytic efficiency of 6-O-maltosyl-beta-cyclodextrin is 16fold higher than that of maltotriose. Compared to the kcat/Km value toward maltotriose, the values for longer substrates such as maltotetraose and maltopentaose are negligible
-
?
maltotriose + H2O
maltose + D-glucose
the enzyme displays dual hydrolysis activity toward alpha-1,4- and alpha-1,6-glycosidic linkages, the catalytic efficiency of 6-O-maltosyl-beta-cyclodextrin is 16fold higher than that of maltotriose. Compared to the kcat/Km value toward maltotriose, the values for longer substrates such as maltotetraose and maltopentaose are negligible
-
?
p-nitrophenylmaltopentaoside + H2O
?
-
catalyzes the release of maltose
-
?
p-nitrophenylmaltopentaoside + H2O
?
catalyzes the release of maltose
-
?
soluble starch + H2O
maltose + ?
the enzyme only releases maltose from polymers such as soluble starch, amylopectin, and glycogen, while maltose is rarely detected from reaction with amylose and pullulan
-
?
soluble starch + H2O
maltose + ?
the enzyme only releases maltose from polymers such as soluble starch, amylopectin, and glycogen, while maltose is rarely detected from reaction with amylose and pullulan
-
?
starch + H2O
?
in vitro breakdown of semicrystalline starch particles by beta-amylases increases significantly if they act together with glucan, water dikinase
-
?
starch + H2O
?
-
starch substrate of different sources, e.g. wheat, wheat bran, rice bran, the enzyme from strain MNU82 utilizes raw and cooked starch
-
?
starch + H2O
?
-
starch substrate of different sources, e.g. wheat, wheat bran, rice bran
-
?
starch + H2O
?
-
beta-amylase hydrolyzes alpha-1,4-linkage, raw starch granules from potato, wheat, rice and corn, with the granules from rice being the best substrate, beta-amylase attacks very slowly on the starch granules, hydrolyzes corn granules efficiently at 45°C
-
?
starch + H2O
?
beta-amylase is an exo-enzyme that catalyzes the hydrolysis of the alpha-1,4-glucosidic linkage of the substrate liberating beta-maltose from the non-reducing end, Glu-172 and Glu-367 are catalytic residues, substrate recognition mechanism, enzyme structure
-
?
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
-
?
starch + H2O
?
catalyzes the hydrolysis of alpha-1,4-glucosidic linkages of soluble starch, and liberates beta-anomeric maltose from the nonreducing ends, exo-acting enzyme, composed of two functional domains, a catalytic domain: domains A and B, and starch-binding domain: domain C, beta-amylase has three carbohydrate-binding sites aside from the active site: two in domain B named Site2 and Site3, one in domain C named Site1, roles of these sites in the catalytic reaction and raw starch-binding, beta-amylase hardly hydrolyzes raw starch from wheat, corn, potato or sweet potato, but binds to it strongly
-
?
starch + H2O
?
hydrolyzes the alpha-1,4-glucosidic linkage liberating beta-maltose from the non-reducing end of substrate, enzyme/domain structure, starch binding site in domain C, catalytic mechanism
-
?
starch + H2O
?
-
starch substrate of different sources, e.g. wheat, wheat bran, rice bran
-
?
starch + H2O
?
-
beta-amylase is an exo-amylase acting on starch with the successive removal of maltose molecules from the non-reducing ends of the glucose polymers with inversion of the anomeric configuration
-
?
starch + H2O
?
-
starch substrate of different sources, e.g. wheat, wheat bran, rice bran
-
?
starch + H2O
?
-
starch substrate of different sources, e.g. wheat, wheat bran, rice bran
-
?
starch + H2O
?
active site structure, Glu-186 and Glu-380 play important roles as general acid and base catalyst, catalyzes the liberation of beta-anomeric maltose from the non-reducing ends
-
?
starch + H2O
?
-
beta-amylase hydrolyzes alpha-1,4-linkage, raw starch granules from potato, wheat, rice and corn, with the granules from rice being the best substrate, no efficient hydrolysis of raw starch granules, very slow enzymic attack
-
?
starch + H2O
?
-
catalyzes the release of maltose from soluble starch, three-dimensional structures of Sd2L and V233A mutant of Sd1
-
?
starch + H2O
?
from potato, catalyzes the release of maltose from the non-reducing ends of starch, three-dimensional structure of Sd2L
-
?
starch + H2O
?
-
starch substrate of different sources, e.g. wheat, wheat bran, rice bran
-
?
starch + H2O
?
-
starch substrate of different sources, e.g. wheat, wheat bran, rice bran
-
?
starch + H2O
?
-
beta-amylase should be a key enzyme in starch degradation during the germination of millet seeds, enzyme activity increases during days 1-4 of germination
-
?
starch + H2O
?
-
106.9% of the activity with amylose, soluble starch, amylose and amylopectin are the most suitable substrates, some activity against native starch, exo-hydrolase that releases beta-maltose from the non-reducing end of alpha-1,4-linked poly- and oligoglucans until the first alpha-1,6-branching point along the substrate molecule is encountered
-
?
starch + H2O
?
-
highest activity, exo-acting enzyme, no production of glucose
-
?
starch + H2O
?
-
starch substrate of different sources, e.g. wheat, wheat bran, rice bran
-
?
starch + H2O
?
Phaffia rhodozyma CECT 1690
-
highest activity, exo-acting enzyme, no production of glucose
-
?
starch + H2O
?
the enzyme is specific for short alpha-glucans. Similar responses to maltose, glycogen, and starch but not to pullulan
-
?
starch + H2O
?
-
starch substrate of different sources, e.g. wheat, wheat bran, rice bran
-
?
starch + H2O
?
-
starch substrate of different sources, e.g. wheat, wheat bran, rice bran
-
?
starch + H2O
?
-
starch substrate of different sources, e.g. wheat, wheat bran, rice bran
-
?
starch + H2O
?
-
starch substrate of different sources, e.g. wheat, wheat bran, rice bran
-
?
starch + H2O
?
-
starch substrate of different sources, e.g. wheat, wheat bran, rice bran
-
?
starch + H2O
?
-
starch substrate of different sources, e.g. wheat, wheat bran, rice bran
-
?
starch + H2O
?
-
starch substrate of different sources, e.g. wheat, wheat bran, rice bran
-
?
starch + H2O
beta-maltose
-
best substrate, pure and low quality starches, maize starch, tapioca starch
maltose is the major end product, traces of maltooligosaccharides, no glucose as product
?
starch + H2O
beta-maltose
-
best substrate, pure and low quality starches, maize starch, tapioca starch
maltose is the major end product, traces of maltooligosaccharides, no glucose as product
?
starch + H2O
beta-maltose
-
beta-amylase is involved in starch degradation during mango ripening, which is clearly triggered by detachment from the mother-plant
-
?
starch + H2O
maltose
enzyme induction upon a cold shock at 4°C leads to starch-dependent maltose accumulation, which might be required for protection of the photosynthetic electron transport chain and sensitization of PSII during freezing, maltose influences the carbohydrate metabolism, overview
-
?
starch + H2O
maltose
-
role of beta-amylase in starch breakdown during temperature stress, product maltose acts as a cryoprotectant and precursor of soluble sugar metabolism, overview
-
?
starch + H2O
maltose
the isozyme is involved in leaf starch degradation
-
?
starch + H2O
maltose
-
millet starch, gelatinization temperature is 61.1-68.7°C
-
?
starch + H2O
maltose
-
in roots during storage, the starch hydrolysis at low temperatures is required for improvement of gustative quality of roots from tuberous-rooted chervil, at higher storage temperature the alpha-amylase activity is increased
-
?
starch + H2O
maltose
-
soluble starch, depolymerization, reaction scheme
-
?
starch + H2O
maltose
-
degradation of starch granules by the enzyme alone occurs at the equatorial grooves of lecticular granules
-
?
starch + H2O
maltose
-
degradation of starch granules by the enzyme alone occurs at the equatorial grooves of lecticular granules
-
?
starch + H2O
maltose
Sorghum sp.
-
Sorghum starch, gelatinization temperature is 70-75°C
-
?
starch + H2O
maltose + ?
catalyzes the release of maltose residues, starch and amylopectin are better substrates than amylose
-
?
additional information
?
-
-
plants mechanism of cold adaptation, enzyme regulation by phytohormones, light, and by abiotic stess, e.g. by osmotic, cold, salt, and drought stress, the enzyme is also regulated by the circadian clock, detailed overview
-
?
additional information
?
-
the isozyme TR-BAMY is redox- and thioredoxin-regulated involving residues C470 and C32 forming a disulfide bridge, the precursor enzyme conatining the transit pepetide is inactive
-
?
additional information
?
-
the isozyme TR-BAMY is redox- and thioredoxin-regulated involving residues C470 and C32 forming a disulfide bridge, the precursor enzyme conatining the transit pepetide is inactive
-
?
additional information
?
-
no hydrolysis of alpha-1,6-glucosidic linkages
-
?
additional information
?
-
-
no hydrolysis of alpha-1,6-glucosidic linkages
-
?
additional information
?
-
beta-amylase does not catalyze a transglycosylation reaction
-
?
additional information
?
-
-
beta-amylase does not catalyze a transglycosylation reaction
-
?
additional information
?
-
analysis of effect of hydroxypropylation and beta-amylase treatment on complexation of debranched starch with naringenin using potato starch and Hylon VII. An increase in hydroxypropylation level improves recovery of soluble complexes, while total recovery remains unchanged. The beta-amylase treatment further increases soluble complex recovery. For the same treatment, the naringenin content is greater in Hylon VII complexes than in potato starch complexes
-
?
additional information
?
-
-
not: xylan, pullulan, cellulose, carboxymethyl cellulose
-
?
additional information
?
-
-
not: xylan, pullulan, cellulose, carboxymethyl cellulose
-
?
additional information
?
-
rhizome beta-amylase is a cytoplasmic vegetative storage protein
-
?
additional information
?
-
-
rhizome beta-amylase is a cytoplasmic vegetative storage protein
-
?
additional information
?
-
beta-amylase exclusively catalyzes the release of beta-maltose from the non-reducing ends of alpha-1,4-linked oligo- and polyglucans, three-dimensional structure
-
?
additional information
?
-
-
beta-amylase exclusively catalyzes the release of beta-maltose from the non-reducing ends of alpha-1,4-linked oligo- and polyglucans, three-dimensional structure
-
?
additional information
?
-
-
soybean trypsin inhibitor and beta-amylase induce rat alveolar macrophages to release nitrogen oxides
-
?
additional information
?
-
-
maltose is the main product of soluble starch hydrolysis
-
?
additional information
?
-
-
maltose is the main product of soluble starch hydrolysis
-
?
additional information
?
-
-
germination markedly increases the beta-amylase
-
?
additional information
?
-
-
beta-amylase is an exo-enzyme that specifically binds to a double (1-4-alpha-D-glucopyranosyl-1-4-alpha-D-glucopyranosyl-) unit from the non-reducing ends of polymaltosidic polysaccharides, and sequentially cleaves glucose disaccharidic units until it encounters any structural variation, producing maltose as sole hydrolysis product
-
?
additional information
?
-
-
no activity with maltotriose and cycloheptaose
-
?
additional information
?
-
-
cysteine, tryptophan and serine are essential amino acids for catalysis, not: maltotriose
-
?
additional information
?
-
Phaffia rhodozyma CECT 1690
-
cysteine, tryptophan and serine are essential amino acids for catalysis, not: maltotriose
-
?
additional information
?
-
-
moderately branched glucans are better substrates than less branched or non-branched or highly branched glucans
-
?
additional information
?
-
the enzyme does not hydrolyze starch, glycogen, pullulan or large maltooligosaccharides
-
?
additional information
?
-
-
the enzyme does not hydrolyze starch, glycogen, pullulan or large maltooligosaccharides
-
?
additional information
?
-
-
germination markedly increases the beta-amylase
-
?
additional information
?
-
-
no activity with pullulan
-
?
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
NATURAL SUBSTRATE
NATURAL PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate)
(Substrate)
LITERATURE
(Substrate)
(Substrate)
COMMENTARY
(Product)
(Product)
LITERATURE
(Product)
(Product)
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
starch + H2O
?
-
beta-amylase is an exo-amylase acting on starch with the successive removal of maltose molecules from the non-reducing ends of the glucose polymers with inversion of the anomeric configuration
-
-
?
starch + H2O
?
-
beta-amylase should be a key enzyme in starch degradation during the germination of millet seeds, enzyme activity increases during days 1-4 of germination
-
-
?
starch + H2O
beta-maltose
-
beta-amylase is involved in starch degradation during mango ripening, which is clearly triggered by detachment from the mother-plant
-
-
?
starch + H2O
maltose
enzyme induction upon a cold shock at 4°C leads to starch-dependent maltose accumulation, which might be required for protection of the photosynthetic electron transport chain and sensitization of PSII during freezing, maltose influences the carbohydrate metabolism, overview
-
-
?
starch + H2O
maltose
-
role of beta-amylase in starch breakdown during temperature stress, product maltose acts as a cryoprotectant and precursor of soluble sugar metabolism, overview
-
-
?
starch + H2O
maltose
the isozyme is involved in leaf starch degradation
-
-
?
starch + H2O
maltose
-
in roots during storage, the starch hydrolysis at low temperatures is required for improvement of gustative quality of roots from tuberous-rooted chervil, at higher storage temperature the alpha-amylase activity is increased
-
-
?
additional information
?
-
-
plants mechanism of cold adaptation, enzyme regulation by phytohormones, light, and by abiotic stess, e.g. by osmotic, cold, salt, and drought stress, the enzyme is also regulated by the circadian clock, detailed overview
-
-
?
additional information
?
-
the isozyme TR-BAMY is redox- and thioredoxin-regulated involving residues C470 and C32 forming a disulfide bridge, the precursor enzyme conatining the transit pepetide is inactive
-
-
?
additional information
?
-
the isozyme TR-BAMY is redox- and thioredoxin-regulated involving residues C470 and C32 forming a disulfide bridge, the precursor enzyme conatining the transit pepetide is inactive
-
-
?
additional information
?
-
rhizome beta-amylase is a cytoplasmic vegetative storage protein
-
-
?
additional information
?
-
-
rhizome beta-amylase is a cytoplasmic vegetative storage protein
-
-
?
additional information
?
-
-
maltose is the main product of soluble starch hydrolysis
-
-
?
additional information
?
-
-
maltose is the main product of soluble starch hydrolysis
-
-
?
additional information
?
-
-
germination markedly increases the beta-amylase
-
-
?
additional information
?
-
-
germination markedly increases the beta-amylase
-
-
?
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
METALS and IONS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
Ca2+
K+
Mg2+
-
activates, maximum enzyme activity of 925.4 U/ml is achieved in the presence of 50 mM Mg2+
NaCl
additional information
Ca2+
activity is increased to 150 % in the presence of calcium chloride
NaCl
-
activates, best at 10-12% activity drops off dramatically at low NaCl concentrations
additional information
the presence or absence of various divalent cations or EDTA had a minimal effect on enzyme activity
additional information
-
the presence or absence of various divalent cations or EDTA had a minimal effect on enzyme activity
additional information
-
no requirement for metal ions
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
2,3-epoxypropyl-alpha-D-glucopyranoside
affinity-labeling reagent, mode of binding, covalently bound to the catalytic residue Glu-172, inactivation mechanism
3,4-epoxybutyl-alpha-D-glucopyranoside
affinity-labeling reagent, mode of binding, covalently bound to the catalytic residue Glu-172
4-chloromercuribenzoate
-
inactivation, the enzyme can be reactivated by L-cysteine
5,5'-dithiobis-(2-nitrobenzoic acid)
-
chemical modification of the exposed sulfhydryl groups in beta-amylase from unmalted seeds with 5,5'-dithiobis-(2-nitrobenzoic acid) results in loss of activity. In the beta-amylase from malted seed the 5,5'-dithiobis-(2-nitrobenzoic acid) chemical modification results in the increase in the KM from 2.81 to 4.14 mg/ml
D-mannose
125 mM, 6% inhibition, p-nitrophenylmaltopentaoside hydrolysis
maltitol
behaves as a mixed-type or competitive inhibitor depending on the chain length of the substrate, inhibition mechanism, binds to Site2 in domain B and forms an abortive ESI complex when amylose is used as substrate
O-alpha-D-glucopyranosyl(1-4)O-alpha-D-glucopyranosyl(1-4)D-xylopyranose
mode of binding in the active site cleft
O-alpha-D-xylopyranosyl(1-4)O-alpha-D-glucopyranosyl(1-4)O-alpha-D-glucopyranoside
mixed-type inhibition, two molecules bind to enzyme
potassium ferricyanide
-
oxidation of the sulfhydryl groups of the enzyme from malted seed in presence of urea results in formation of a dimeric enzyme. The oxidative dimerization leads to inactivation of the enzyme
Ag+
-
1 mM, almost complete inhibition of mutant enzyme M185L/S295A/I297V/S350P/S351P/Q352D/A376S
beta-amylase-inhibitor
-
several strains of Streptomyces produce a beta-amylase inhibitor when grown on a medium containing starch and deoxynojirimycin
-
beta-amylase-inhibitor
-
several strains of Streptomyces produce a beta-amylase inhibitor when grown on a medium containing starch and deoxynojirimycin
-
beta-amylase-inhibitor
-
several strains of Streptomyces produce a beta-amylase inhibitor when grown on a medium containing starch and deoxynojirimycin
-
beta-amylase-inhibitor
-
several strains of Streptomyces produce a beta-amylase inhibitor when grown on a medium containing starch and deoxynojirimycin
-
beta-amylase-inhibitor
-
several strains of Streptomyces produce a beta-amylase inhibitor when grown on a medium containing starch and deoxynojirimycin
-
Cd2+
-
1 mM, almost complete inhibition of barley enzyme and recombinant enzyme, less inhibitory towards mutant enzyme M185L/S295A/I297V/S350P/S351P/Q352D/A376S
Cu2+
-
1 mM, almost complete inhibition of mutant enzyme M185L/S295A/I297V/S350P/S351P/Q352D/A376S
D-glucose
p-nitrophenylmaltopentaoside hydrolysis: 125 mM, 87.5% inhibition, iodine staining method: mixed-type, weak inhibition compared with maltose and cyclohexaamylose
EDTA
1 mM, 42% loss of activity. 5-10 mM, complete loss of activity
Hg2+
-
1 mM, almost complete inhibition of mutant enzyme M185L/S295A/I297V/S350P/S351P/Q352D/A376S
maltose
p-nitrophenylmaltopentaoside hydrolysis: 125 mM, 87.5% inhibition, iodine staining method: competitive inhibition
p-chloromercuribenzoate
-
1 mM, 97% inhibition, exogenous thiols like dithiothreitol, 2-mercaptoethanol or cysteine HCl reactivate
PCMB
-
0.5 mM, 75% loss of activity after 30 min at 22°C, cysteine reactivates
PCMB
-
0.1 mM, complete inhibition of mutant enzyme M185L/S295A/I297V/S350P/S351P/Q352D/A376S
PCMB
-
0.001-0.1 mM, inactivation is partly reversed by adding 10fold to 20fold excess of glutathione or 1,2-dithiopropanol
Zn2+
-
1 mM, almost complete inhibition of barley enzyme and recombinant enzyme, less inhibitory towards mutant enzyme M185L/S295A/I297V/S350P/S351P/Q352D/A376S
additional information
the 41 amino acid transit peptide inhibits isozyme TR-BAMY
-
additional information
the 41 amino acid transit peptide inhibits isozyme TR-BAMY
-
additional information
-
no or poor effect by boric acid and urea at 1-10 mM
-
additional information
-
PMSF and 2-mercaptoethanol have no significant effect on the amylase activity
-
additional information
-
the synthesis of beta-amylase is repressed by glucose, fructose or sucrose as carbon source, not inhibited by EDTA
-
additional information
-
no inhibition by 4-chloromercuribenzoate, heavy metal ions, nor Schardinger dextrins
-
additional information
no considerable effect of organic solvents (ethanol, methanol, isopropanol, acetone and n-butanol) is observed on enzyme activity
-
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ACTIVATING COMPOUND
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
polyethylene glycol 1000
-
1500 Da PEG, increases the enzyme activity by 60% at 0.02% w/v
polyethylene glycol 1500
-
1500 Da PEG, increases the enzyme activity by 77% at 0.02% w/v
-
polyethylene glycol 2000
-
1500 Da PEG, increases the enzyme activity by 58% at 0.02% w/v
polyethylene glycol 400
-
1500 Da PEG, increases the enzyme activity by 7% at 0.02% w/v
-
polyethylene glycol 4600
-
1500 Da PEG, increases the enzyme activity by 74% at 0.02% w/v
polyethylene glycol 600
-
1500 Da PEG, increases the enzyme activity by 19% at 0.02% w/v
polyethylene glycol 8000
-
1500 Da PEG, increases the enzyme activity by 68% at 0.02% w/v
polyvinyl alcohol
-
10 kDa: increases the enzyme activity by 36% at 0.02% w/v, 50 kDa: increases the enzyme activity by 21% at 0.02% w/v
thioredoxin
thioredocins f1, m1, and y1, the isozyme TR-BAMY is positively thioredoxin-regulated
additional information
-
cold stress activates the chloroplastic isozyme by 5fold at 3°C
-
additional information
the enzyme is induced during low temperature stress at 4°C
-
additional information
the enzyme requires reducing conditions for full activity
-
additional information
the enzyme requires reducing conditions for full activity
-
additional information
-
phenylmethanesulfonyl fluoride does not show any effect on enzyme activity
-
additional information
-
low temperature of 4°C rapidly induces the enzyme activity
-
additional information
-
the synthesis of beta-amylase is induced by starch and maltose
-
additional information
-
rapid induction of type II beta-amylase by nitric oxide, from sodium nitroprusside, but not by gibberellin in seeds during the early stage of germination, sodium nitroprusside also directly induces the release of the enzyme from glutenin
-
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KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.491
amylose
-
DP = 17, mutant enzyme M185L/S295A/I297V/S350P/S351P/Q352D/A376S
0.6
amylose
pH 7, 25°C, DPn: 16, S235A/Y249A/W449F/W495F quadruple mutant
0.0083
starch
-
pH 5, 40°C, soluble starch, wild-type Sd2H and V233A/L347S double mutant of Sd2L
additional information
additional information
-
Km: 1.25 mg/ml for starch
-
additional information
additional information
-
Km: 3 mg/ml for soluble starch
-
additional information
additional information
-
the Km-value for linear maltodextrins decreases with chain-lengths up to about 50 glucose units and with longer chain lengths it remains constant at about 0.14 mM
-
additional information
additional information
-
Km for soluble starch is 0.4%
-
additional information
additional information
-
5.9 mg/ml for soluble starch, light amylase. 6.8 mg/ml for soluble starch for soluble starch, heavy amylase
-
additional information
additional information
-
Km: 2.25 mg/ml for amylopectin for isoenzyme 2, Km: 1.65 mg/ml for amylopectin, isoenzyme 6
-
additional information
additional information
-
Km: 2.29 mg/ml for soluble starch at 60°C, 1.68 mg/ml for soluble starch at 75°C
-
additional information
additional information
-
Km: 1.67 mg/ml for soluble starch
-
additional information
additional information
beta-amylase from germinated barley has a higher substrate binding affinity for starch than enzyme from mature grain, removal of the four C-terminal glycine-rich repeats enhances the substrate binding affinity, kinetic parameters for several deletion mutants
-
additional information
additional information
-
beta-amylase from germinated barley has a higher substrate binding affinity for starch than enzyme from mature grain, removal of the four C-terminal glycine-rich repeats enhances the substrate binding affinity, kinetic parameters for several deletion mutants
-
additional information
additional information
binding parameters of wild-type and mutant enzymes to raw corn starch
-
additional information
additional information
-
binding parameters of wild-type and mutant enzymes to raw corn starch
-
additional information
additional information
kinetic parameters for wild-type and mutant SBA
-
additional information
additional information
-
kinetic parameters for wild-type and mutant SBA
-
additional information
additional information
-
Km for starch is 4.34 mg/ml at 60°C
-
additional information
additional information
-
the 3 allelic forms of beta-amylase Sd1, Sd2H and Sd2L exhibit different kinetic properties, an R115C mutation is responsible for this difference
-
additional information
additional information
-
kinetics, isothermal titration microcalorimetric method
-
additional information
additional information
kinetics, recombinant wild-type andmutant enzymes
-
additional information
additional information
-
kinetics, recombinant wild-type andmutant enzymes
-
additional information
additional information
-
13.6 mg/l, starch as substrate
-
additional information
additional information
-
Km and Vmax values are 79.37mg/ml and 5.13 U/ml, respectively, at 50°C, pH 6.0, Michaelis-Menten kinetics
-
additional information
additional information
-
Michaelis-Menten kinetics and Lineweaver-Burk plots, Km and Vmax values at 50°C are estimated to be 2.81 mg/ml and 10.62 U/min, respectively
-
additional information
additional information
Michaelis-Menten kinetics, modelling
-
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TURNOVER NUMBER [1/s]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
308
starch
-
pH 5, 40°C, soluble starch, wild-type Sd2H and V233A/L347S double mutant of Sd2L
additional information
additional information
kinetic parameters for several deletion mutants
-
additional information
additional information
-
kinetic parameters for several deletion mutants
-
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kcat/KM VALUE [1/mMs-1]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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Ki VALUE [mM]
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.45
O-alpha-D-xylopyranosyl(1-4)O-alpha-D-glucopyranosyl(1-4)O-alpha-D-glucopyranoside
pH 7, 25°C, wild-type enzyme, amylose as substrate
0.8
cyclohexaamylose
pH 7, 25°C, wild-type enzyme, amylose as substrate
5.1
maltitol
pH 7, 25°C, S235A/Y249A double mutant, amylose as substrate
5.7
maltitol
pH 7, 25°C, S235A/Y249A/W449F/W495F quadruple mutant, amylose as substrate
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SPECIFIC ACTIVITY [µmol/min/mg]
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
19.99
-
TPP-interfacial precipitate enzyme after dialysis and lyophilisation, pH 6.0, 50°C
2182
purified commercial preparation, pH and temperature not specified in the publication
45.95
Sorghum sp.
-
96 h germination, the enzyme activity increases progressively during seed germination, overview
additional information
additional information
-
BAM-2 specific activity is 25fold lower than that of BAM-3 and 50fold lower than that of BAM-1. No activity is detectable for recombinant BAM-4 protein
additional information
-
the enzyme activity increases progressively during seed germination, different cultivars, activity in phoshate buffer extracts, the activity is decreased in hot water extracts, and highly decreased in cold water extracts, overview the hot water extracts show higher activity due to gelatinization of the starch grains
additional information
-
catalytic activity of the enzyme at different pressure/temperature conditions, up to 700 mPa, 20-70°C, overview
additional information
very low activity in different cultivars of varieties japonica and japonica x indica, i.e. Nipponbare x Kasalath, the Nipponbare allele highly suppresses the enzyme, quantitative activity and expression analysis
additional information
very low activity in different cultivars of varieties japonica and japonica x indica, i.e. Nipponbare x Kasalath, the Nipponbare allele highly suppresses the enzyme, quantitative activity and expression analysis
additional information
Sorghum sp.
-
different increase in activities during seed germination in the different Sorghum sp. varieties, overview
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pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
4.8
5.4
5.5
5.5 - 6
5.6
6.2
6.5
6.9
7.5
additional information
5.4
hydrolysis of potato amylopectin, at 37°C, the reduced pKa-value of Glu-380 is stabilized by the hydrogen bond network and is responsible for the lower pH-optimum of soybean beta-amylase compared with that of Bacillus cereus, pH 6.7
additional information
the isozyme TR-BAMY shifts between an active and an inactive form dependent on the pH
additional information
the isozyme TR-BAMY shifts between an active and an inactive form dependent on the pH
additional information
comparison of pH-dependency/pH-profiles of recombinant wild-type and mutant enzymes
additional information
-
comparison of pH-dependency/pH-profiles of recombinant wild-type and mutant enzymes
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pH RANGE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
2 - 8
-
pH 2.0: about 35% of maximal activity, pH 8.0: about 30% of maximal activity
3 - 7.2
-
50% of maximal activity at pH 3.0 and pH 7.2, degradation of glycogen
3 - 8
3 - 8.5
-
pH 3.0: about 30% of maximal activity, pH 8.5: about 40% of maximal activity
3 - 9
4 - 6
pH 4.0: about 85% of maximal activity, pH 6.0: about 60% of maximal activity, alpha-1,4-glycosidic linkage hydrolysis of maltotriose
4 - 7
Dioscorea batatus
-
pH 4.0: about 25% of maximal activity, pH 7.0: about 50% of maximal activity
4 - 8
4.5 - 8.5
-
pH 4.5: about 40% of maximal activity, pH 8.5: about 60% of maximal activity
5 - 6
-
more than 80% of maximal activity at pH 5.0 and at pH 6.0
5 - 8
-
pH 5.0: about 55% of maximal activity, pH 8.0: about 60% of maximal activity
5.5 - 10
-
pH 5.5.: about 50% of maximal activity, pH 10.0: about 40% of maximal activity
3 - 8
-
pH 3.0: about 35% of maximal activity, pH 8.0: about 70% of maximal activity
3 - 8
-
pH 3.0: about 50% of maximal activity, pH 8.0: about 55% of maximal activity
3 - 8
-
pH 3.0: about 70% of maximal activity, pH 8.0: about 60% of maximal activity
3 - 9
-
pH 3.0: about 50% of maximal activity, pH 9.0: about 40% of maximal activity
3 - 9
-
pH 3.0: about 70% of maximal activity, pH 9.0: about 15% of maximal activity
4 - 8
immobilized enzyme, over 50% of maximal activity within this range
4 - 8
-
pH 4.0: about 65% of maximal activity, pH 8.0: about 55% of maximal activity
4 - 8
pH 4.0: about 50% of maximal activity, pH 8.0: about 70% of maximal activity, alpha-1,6-glycosidic linkage hydrolysis of 6-O-maltotetraosyl-beta-cyclodextrin
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TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
25
35
37
40
45
50
55
60
70
75
85