Any feedback?
Please rate this page
(literature.php)
(0/150)

BRENDA support

Literature summary for 3.2.1.2 extracted from

  • Hirata, A.; Adachi, M.; Sekine, A.; Kang, Y.N.; Utsumi, S.; Mikami, B.
    Structural and enzymatic analysis of soybean beta-amylase mutants with increased pH optimum (2004), J. Biol. Chem., 279, 7287-7295.
    View publication on PubMed
Search for more literature for 3.2.1.2

Crystallization (Commentary)

Crystallization (Comment) Organism
wild-type, M51T, E178Y and N340T mutant SBA, complexed with maltose, hanging-drop vapor diffusion method, X-ray analysis Glycine max

Protein Variants

Protein Variants Comment Organism
E178Y kinetic data, 43% of specific activity of wild-type SBA, the pH-optimum of mutant enzyme is shifted to pH 6, the hydrogen bond between Glu-380 and Asn-340 is completely disrupted, mutant SBA structure Glycine max
M51T kinetic data, 11% of specific activity of wild-type SBA, the pH-optimum of mutant enzyme is shifted to pH 6.5, the hydrogen bonds between Glu-380 and Asn-340 and between Glu-380 and Lys-295 are completely disrupted, mutant SBA structure Glycine max
N340T kinetic data, 32% of specific activity of wild-type SBA, the pH-optimum of mutant enzyme is shifted to pH 6.6, the hydrogen bond between Glu-380 and Asn-340 is completely disrupted, mutant SBA structure Glycine max

KM Value [mM]

KM Value [mM] KM Value Maximum [mM] Substrate Comment Organism Structure
additional information
-
 additional information kinetic parameters for wild-type and mutant SBA Glycine max

Organism

Organism UniProt Comment Textmining
Glycine max P10538
-
-

Purification (Commentary)

Purification (Comment) Organism
mutant beta-amylases Glycine max

Specific Activity [micromol/min/mg]

Specific Activity Minimum [µmol/min/mg] Specific Activity Maximum [µmol/min/mg] Comment Organism
additional information
-
-
 Glycine max

Substrates and Products (Substrate)

Substrates Comment Substrates Organism Products Comment (Products) Rev. Reac.
amylopectin + H2O from potato, active site structure, Glu-186 and Glu-380 play important roles as general acid and base catalyst Glycine max ?
-
 ?
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 Glycine max ?
-
 ?

Synonyms

Synonyms Comment Organism
SBA soybean beta-amylase Glycine max

pH Optimum

pH Optimum Minimum pH Optimum Maximum Comment Organism
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 Glycine max