Literature summary for 3.2.1.1 extracted from

Liao, S.M.; Liang, G.; Zhu, J.; Lu, B.; Peng, L.X.; Wang, Q.Y.; Wei, Y.T.; Zhou, G.P.; Huang, R.B.
Influence of calcium ions on the thermal characteristics of alpha-amylase from thermophilic Anoxybacillus sp. GXS-BL (2019), Protein Pept. Lett., 26, 148-157 .

Search for more literature for 3.2.1.1

Cloned(Commentary)

Cloned (Comment)	Organism
recombinant expression of His-tagged enzyme in Escherichia coli strain M15	Anoxybacillus sp. GXS-BL

Metals/Ions

Metals/Ions	Comment	Organism	Structure
Ca2+	Ca2+ ions have effects on the structure and thermal propeties of alpha-amylase (AGXA) from thermophilic Anoxybacillus sp. strain GXS-BL. With calcium ions, the values of Topt, T50, t1/2, Tm and DELTAH in enzyme AGXA are significantly higher than those of enzyme AGXA without calcium ions, showing calcium ions have stabilizing effects on alpha-amylase structure with the increased temperature. Four Ca2+ ions (Ca1-4)are bound to the model structure. Ca1 is in the region between domain A and domain B, coordinated by the N139, D182, H217, and E173 residues and three water molecules. Ca2 and Ca3 are both located in domain A, with Ca2 coordinated by the N44, N46, N49, D50, G63, and D65 residues and a water molecule, and Ca3 coordinated by the N92, E109, and E110 residues and three water molecules. Ca4 is in the region between domain A and domain C, coordinated by the E400 residue and five water molecules	Anoxybacillus sp. GXS-BL

Molecular Weight [Da]

Molecular Weight [Da]	Molecular Weight Maximum [Da]	Comment	Organism
55000	-	recombinant His-tagged enzyme, gel filtration	Anoxybacillus sp. GXS-BL

Organism

Organism	UniProt	Comment	Textmining
Anoxybacillus sp. GXS-BL	G4Y5W9	-	-

Purification (Commentary)

Purification (Comment)	Organism
recombinant His-tagged enzyme from Escherichia coli strain M15 by nickel affinity chromatography and gel filtration	Anoxybacillus sp. GXS-BL

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.	Reac.
soluble starch + H2O	1% w/v starch solution	Anoxybacillus sp. GXS-BL	?	-	?

Subunits

Subunits	Comment	Organism
?	x * 55000, recombinant His-tagged enzyme, SDS-PAGE	Anoxybacillus sp. GXS-BL

Synonyms

Synonyms	Comment	Organism
AGXA	-	Anoxybacillus sp. GXS-BL

Temperature Optimum [°C]

Temperature Optimum [°C]	Temperature Optimum Maximum [°C]	Comment	Organism
40	-	-	Anoxybacillus sp. GXS-BL

Temperature Range [°C]

Temperature Minimum [°C]	Temperature Maximum [°C]	Comment	Organism
40	80	activity range in presence of Ca2+, profile overview	Anoxybacillus sp. GXS-BL
40	70	activity range in absence of Ca2+, profile overview	Anoxybacillus sp. GXS-BL

Temperature Stability [°C]

Temperature Stability Minimum [°C]	Temperature Stability Maximum [°C]	Comment	Organism
additional information	-	with calcium ions, the values of Topt, T50, t1/2, Tm and DELTAH in enzyme AGXA are significantly higher than those of enzyme AGXA without calcium ions, showing calcium ions have stabilizing effects on alpha-amylase structure with the increased temperature. AGXA undergoes thermal denaturation via a two-state irreversible unfolding process. AGXA without calcium ions exhibits two transition states upon unfolding, including alpha-helical contents increasing, and the transition from alpha-helices to beta-sheet structures, which is obviously different in AGXA with Ca2+ ions, and up to 4 Ca2+ ions are located on the interdomain or intradomain regions according to the modeling structure	Anoxybacillus sp. GXS-BL
55	75	purified recombinant His-tagged enzyme, T50 value of AGXA with calcium ions is 73.8°C, T50 value of AGXA without calcium ions is 63.5°C	Anoxybacillus sp. GXS-BL

pH Optimum

pH Optimum Minimum	pH Optimum Maximum	Comment	Organism
8	-	assay at	Anoxybacillus sp. GXS-BL

pH Stability

pH Stability	pH Stability Maximum	Comment	Organism
6	9.5	purified recombinant His-tagged enzyme, 30 min, over 70% activity remaining	Anoxybacillus sp. GXS-BL

General Information

General Information	Comment	Organism
additional information	three-dimensional structure determination of enzyme AGXA by homology modelling using alpha-amylase (PDB ID 5A2A) as the template	Anoxybacillus sp. GXS-BL

Use of this online version of BRENDA is free under the CC BY 4.0 license. See terms of use for full details.

Release 2023.1 (January 2023)