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

BRENDA support

Literature summary for 3.2.1.23 extracted from

  • Coker, J.A.; Brenchley, J.E.
    Protein engineering of a cold-active beta-galactosidase from Arthrobacter sp. SB to increase lactose hydrolysis reveals new sites affecting low temperature activity (2006), Extremophiles, 10, 515-524.
    View publication on PubMed
Search for more literature for 3.2.1.23

Cloned(Commentary)

Cloned (Comment) Organism
expression of His6-tagged BgaS enzyme and mutant variants in Escherichia coli strain MC1061 (DE3) Arthrobacter sp.

Protein Variants

Protein Variants Comment Organism
E229D site-directed mutagenesis, enzyme BgaS7a, the mutant shows slightly increased activity compared to the wild-type enzyme Arthrobacter sp.
E229D/G803D site-directed mutagenesis, inactive mutant Arthrobacter sp.
E229D/V405A site-directed mutagenesis, enzyme BgaS7, the mutant shows similar thermal optima and thermostabilities as BgaS, but shows a 2.5fold increase in catalytic activity at 15°C and hydrolyzes 80% of lactose in skim milk in less than half the time of BgaS at 2.5°C Arthrobacter sp.
E229D/V405A/G803D site-directed mutagenesis, enzyme BgaS6, the mutant shows similar thermal optima and thermostabilities as BgaS, the mutant shows slightly increased activity compared to the wild-type enzyme Arthrobacter sp.
G803D site-directed mutagenesis, inactive mutant Arthrobacter sp.
additional information gene bgaS3 encoding a loss of function variant is subjected to random mutagenesis to restore activity and discover potential interactions important in cold activity Arthrobacter sp.
V405A site-directed mutagenesis, enzyme BgaS7b, the mutant shows slightly increased activity compared to the wild-type enzyme Arthrobacter sp.
V405A/G803D site-directed mutagenesis, inactive mutant Arthrobacter sp.

Inhibitors

Inhibitors Comment Organism Structure
D-galactose product inhibition Arthrobacter sp.
lactose substrate inhibition Arthrobacter sp.

KM Value [mM]

KM Value [mM] KM Value Maximum [mM] Substrate Comment Organism Structure
additional information
-
 additional information temperature dependence of kinetics of wild-type and mutant enzymes, overview Arthrobacter sp.
7.5
-
 lactose 15°C, recombinant mutant BgaS7, i.e. E229D/V405A Arthrobacter sp.
11.5
-
 lactose 15°C, recombinant wild-type BgaS Arthrobacter sp.
12.7
-
 lactose 15°C, recombinant mutant BgaS6, i.e.E229D/V405A/G803D Arthrobacter sp.

Metals/Ions

Metals/Ions Comment Organism Structure
Mg2+ the enzyme requires metal ions, Mg2+ or Mn2+ can restore the enzyme activity of recombinant wild-type and mutant apoenzymes, but not Ca2+, Cu2+, and Na+, overview Arthrobacter sp.
Mn2+ the enzyme requires metal ions, Mg2+ or Mn2+ can restore the enzyme activity of recombinant wild-type and mutant apoenzymes, but not Ca2+, Cu2+, and Na+, overview Arthrobacter sp.

Natural Substrates/ Products (Substrates)

Natural Substrates Organism Comment (Nat. Sub.) Natural Products Comment (Nat. Pro.) Rev. Reac.
lactose + H2O Arthrobacter sp.
-
 D-glucose + D-galactose
-
 ?
lactose + H2O Arthrobacter sp. SB
-
 D-glucose + D-galactose
-
 ?

Organism

Organism UniProt Comment Textmining
Arthrobacter sp.
-
 gene bgaS encoding a cold-active enzyme
-
Arthrobacter sp. SB
-
 gene bgaS encoding a cold-active enzyme
-

Specific Activity [micromol/min/mg]

Specific Activity Minimum [µmol/min/mg] Specific Activity Maximum [µmol/min/mg] Comment Organism
additional information
-
 substrate specificity of recombinant wild-type and mutant enzymes, overview Arthrobacter sp.

Substrates and Products (Substrate)

Substrates Comment Substrates Organism Products Comment (Products) Rev. Reac.
2-nitrophenyl beta-D-galactopyranoside + H2O
-
 Arthrobacter sp. 2-nitrophenol + beta-D-galactose
-
 ?
2-nitrophenyl beta-D-galactopyranoside + H2O
-
 Arthrobacter sp. SB 2-nitrophenol + beta-D-galactose
-
 ?
4-nitrophenyl beta-D-galactopyranoside + H2O
-
 Arthrobacter sp. 4-nitrophenol + beta-D-galactose
-
 ?
4-nitrophenyl beta-D-galactopyranoside + H2O
-
 Arthrobacter sp. SB 4-nitrophenol + beta-D-galactose
-
 ?
5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside + H2O
-
 Arthrobacter sp. 5-bromo-4-chloroindol + beta-D-galactose
-
 ?
5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside + H2O
-
 Arthrobacter sp. SB 5-bromo-4-chloroindol + beta-D-galactose
-
 ?
lactose + H2O
-
 Arthrobacter sp. D-glucose + D-galactose
-
 ?
lactose + H2O
-
 Arthrobacter sp. SB D-glucose + D-galactose
-
 ?
additional information substrate specificity of recombinant wild-type and mutant enzymes, overview Arthrobacter sp. ?
-
 ?
additional information substrate specificity of recombinant wild-type and mutant enzymes, overview Arthrobacter sp. SB ?
-
 ?

Subunits

Subunits Comment Organism
tetramer three-dimensional structure modeling of BgaS, homotetramer that forms a diamond shape with two axes: a long interface and an activating interface, overview Arthrobacter sp.

Synonyms

Synonyms Comment Organism
BgaS
-
 Arthrobacter sp.

Temperature Optimum [°C]

Temperature Optimum [°C] Temperature Optimum Maximum [°C] Comment Organism
-
 20 assay at, cold-active enzyme Arthrobacter sp.

Temperature Range [°C]

Temperature Minimum [°C] Temperature Maximum [°C] Comment Organism
-
 20
-
 Arthrobacter sp.

Temperature Stability [°C]

Temperature Stability Minimum [°C] Temperature Stability Maximum [°C] Comment Organism
additional information
-
 thermostability of recombinant wild-type and mutant enzymes, overview Arthrobacter sp.
30
-
 BgaS, mutant BgaS7, and mutant BgaS6 loose all detectable activity after 75, 90, and 120 min, respectively Arthrobacter sp.
37
-
 10 min, inactivation Arthrobacter sp.
60
-
 10 min, inactivation Arthrobacter sp.

Turnover Number [1/s]

Turnover Number Minimum [1/s] Turnover Number Maximum [1/s] Substrate Comment Organism Structure
4.1
-
 lactose 15°C, recombinant mutant BgaS7, i.e. E229D/V405A Arthrobacter sp.
5.3
-
 lactose 15°C, recombinant wild-type BgaS Arthrobacter sp.
18.7
-
 lactose 15°C, recombinant mutant BgaS6, i.e.E229D/V405A/G803D Arthrobacter sp.

Ki Value [mM]

Ki Value [mM] Ki Value maximum [mM] Inhibitor Comment Organism Structure
additional information
-
 additional information temperature dependence of inhibition kinetics of wild-type and mutant enzymes, overview Arthrobacter sp.