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

BRENDA support

Literature summary extracted from

  • Holmes, M.L.; Scopes, R.K.; Moritz, R.L.; Simpson, R.J.; Englert, C.; Pfeifer, F.; Dyall-Smith, M.L.
    Purification and analysis of an extremely halophilic beta-galactosidase from Haloferax alicantei (1997), Biochim. Biophys. Acta, 1337, 276-286.
    View publication on PubMed

Protein Variants

EC Number Protein Variants Comment Organism
3.2.1.23 additional information an overproducing mutant is isolated by UV mutagenesis and screening on agar plates containing X-Gal substrate. Cytoplasmic extracts of the mutant contain 25fold higher enzyme levels than the parent Haloferax lucentense
3.2.1.38 additional information an overproducing mutant is isolated by UV mutagenesis and screening on agar plates containing X-Gal substrate. Cytoplasmic extracts of the mutant contain 25fold higher enzyme levels than the parent Haloferax lucentense

General Stability

EC Number General Stability Organism
3.2.1.23 activity is irreversibly lost within min in low salt buffers, below 0.5 M Haloferax lucentense
3.2.1.38 activity is irreversibly lost within min in low salt buffers, below 0.5 M Haloferax lucentense

Inhibitors

EC Number Inhibitors Comment Organism Structure
3.2.1.23 Cu2+ 1 mM Haloferax lucentense
3.2.1.23 EDTA 5-20 mM Haloferax lucentense
3.2.1.23 glycerol interferes with enzyme activity Haloferax lucentense
3.2.1.23 additional information loss in activity if dithiothreitol or 2-mercaptoethanol is omitted from buffers although this effect appears to be reversible, indicating the presence of an active thiol in the enzyme Haloferax lucentense
3.2.1.23 Zn2+ 1 mM Haloferax lucentense
3.2.1.38 Cu2+ 1 mM Haloferax lucentense
3.2.1.38 EDTA 5-20 mM Haloferax lucentense
3.2.1.38 glycerol interferes with enzyme activity Haloferax lucentense
3.2.1.38 additional information loss in activity if dithiothreitol or 2-mercaptoethanol is omitted from buffers although this effect appears to be reversible, indicating the presence of an active thiol in the enzyme Haloferax lucentense
3.2.1.38 Zn2+ 1 mM Haloferax lucentense

KM Value [mM]

EC Number KM Value [mM] KM Value Maximum [mM] Substrate Comment Organism Structure
3.2.1.23 0.87
-
 2-nitrophenyl beta-D-galactoside pH 7.2, 22°C, the enzyme also shows beta-fucosidase activity Haloferax lucentense
3.2.1.38 0.87
-
 2-nitrophenyl beta-D-galactoside pH 7.2, 22°C, the enzyme also shows beta-fucosidase activity Haloferax lucentense

Metals/Ions

EC Number Metals/Ions Comment Organism Structure
3.2.1.23 KCl the activity of the enzyme in 2.5 M and 4 M KCl relative to 4 M NaCl is 34% and 40%, respectively Haloferax lucentense
3.2.1.23 NaCl optimally active at 4 M NaCl Haloferax lucentense
3.2.1.38 KCl the activity of the enzyme in 2.5 M and 4 M KCl relative to 4 M NaCl is 34% and 40%, respectively Haloferax lucentense
3.2.1.38 NaCl optimally active at 4 M NaCl Haloferax lucentense

Molecular Weight [Da]

EC Number Molecular Weight [Da] Molecular Weight Maximum [Da] Comment Organism
3.2.1.23 78000
-
 2 * 78000, SDS-PAGE Haloferax lucentense
3.2.1.23 180000
-
 gel filtration Haloferax lucentense
3.2.1.38 78000
-
 2 * 78000, SDS-PAGE Haloferax lucentense
3.2.1.38 180000
-
 gel filtration Haloferax lucentense

Organic Solvent Stability

EC Number Organic Solvent Comment Organism
3.2.1.23 Glycerol 20% v/v, stabilizes the enzyme in buffers with no salt Haloferax lucentense
3.2.1.23 sorbitol 30% v/v, stabilizes the enzyme in buffers with no salt. The enzyme is stable in 30% sorbitol for at least four months at -20°C, but at room temperature approximately 20% of specific activity is lost after 48 h Haloferax lucentense
3.2.1.38 Glycerol 20% v/v, stabilizes the enzyme in buffers with no salt Haloferax lucentense
3.2.1.38 sorbitol 30% v/v, stabilizes the enzyme in buffers with no salt. The enzyme is stable in 30% sorbitol for at least four months at -20°C, but at room temperature approximately 20% of specific activity is lost after 48 h Haloferax lucentense

Organism

EC Number Organism UniProt Comment Textmining
3.2.1.23 Haloferax lucentense P94804
-
-
3.2.1.23 Haloferax lucentense DSM 14919 P94804
-
-
3.2.1.38 Haloferax lucentense P94804
-
-
3.2.1.38 Haloferax lucentense DSM 14919 P94804
-
-

Purification (Commentary)

EC Number Purification (Comment) Organism
3.2.1.23
-
 Haloferax lucentense
3.2.1.38
-
 Haloferax lucentense

Specific Activity [micromol/min/mg]

EC Number Specific Activity Minimum [µmol/min/mg] Specific Activity Maximum [µmol/min/mg] Comment Organism
3.2.1.23 42
-
 substrate: 2-nitrophenyl-beta D-galactoside, pH 7.2, 22°C, the enzyme also shows beta-fucosidase activity Haloferax lucentense
3.2.1.38 42
-
 substrate: 2-nitrophenyl beta-D-galactosidepH 7.2, 22°C, the enzyme also shows beta-fucosidase activity Haloferax lucentense

Storage Stability

EC Number Storage Stability Organism
3.2.1.23 -20°C, 50% loss of activity when stored overnight Haloferax lucentense
3.2.1.23 4°C, 18% loss of activity when stored overnight Haloferax lucentense
3.2.1.38 -20°C, 50% loss of activity when stored overnight Haloferax lucentense
3.2.1.38 4°C, 18% loss of activity when stored overnight Haloferax lucentense

Substrates and Products (Substrate)

EC Number Substrates Comment Substrates Organism Products Comment (Products) Rev. Reac.
3.2.1.23 2-nitrophenyl beta-D-galactoside + H2O the enzyme also shows beta-fucosidase activity Haloferax lucentense 2-nitrophenol + beta-D-galactose
-
 ?
3.2.1.23 4-nitrophenyl beta-D-fucopyranoside + H2O 43% relative to 2-nitrophenyl-beta-D-galactoside hydrolysis Haloferax lucentense 4-nitrophenol + beta-D-fucose
-
 ?
3.2.1.23 lactulose + H2O the enzyme also shows beta-fucosidase activity Haloferax lucentense D-galactose + D-fructose
-
 ?
3.2.1.23 additional information no beta-glucosidase, beta-arabinosidase or beta-xylosidase activity can be detected Haloferax lucentense ?
-
 ?
3.2.1.23 additional information no beta-glucosidase, beta-arabinosidase or beta-xylosidase activity can be detected Haloferax lucentense DSM 14919 ?
-
 ?
3.2.1.38 2-nitrophenyl beta-D-galactoside + H2O the enzyme also shows beta-fucosidase activity Haloferax lucentense 2-nitrophenol + beta-D-galactose
-
 ?
3.2.1.38 2-nitrophenyl beta-D-galactoside + H2O the enzyme also shows beta-fucosidase activity Haloferax lucentense DSM 14919 2-nitrophenol + beta-D-galactose
-
 ?
3.2.1.38 4-nitrophenyl beta-D-fucopyranoside + H2O 43% relative to 2-nitrophenyl-beta-D-galactoside hydrolysis Haloferax lucentense 4-nitrophenol + beta-D-fucose
-
 ?
3.2.1.38 4-nitrophenyl beta-D-fucopyranoside + H2O 43% relative to 2-nitrophenyl-beta-D-galactoside hydrolysis Haloferax lucentense DSM 14919 4-nitrophenol + beta-D-fucose
-
 ?
3.2.1.38 lactulose + H2O the enzyme also shows beta-fucosidase activity Haloferax lucentense D-galactose + D-fructose
-
 ?
3.2.1.38 lactulose + H2O the enzyme also shows beta-fucosidase activity Haloferax lucentense DSM 14919 D-galactose + D-fructose
-
 ?
3.2.1.38 additional information no beta-glucosidase, beta-arabinosidase or beta-xylosidase activity can be detected Haloferax lucentense ?
-
 ?
3.2.1.38 additional information no beta-glucosidase, beta-arabinosidase or beta-xylosidase activity can be detected Haloferax lucentense DSM 14919 ?
-
 ?

Subunits

EC Number Subunits Comment Organism
3.2.1.23 dimer 2 * 78000, SDS-PAGE Haloferax lucentense
3.2.1.38 dimer 2 * 78000, SDS-PAGE Haloferax lucentense

Temperature Optimum [°C]

EC Number Temperature Optimum [°C] Temperature Optimum Maximum [°C] Comment Organism
3.2.1.23 22
-
 assay at room temperature Haloferax lucentense
3.2.1.38 22
-
 assay at room temperature Haloferax lucentense

Temperature Stability [°C]

EC Number Temperature Stability Minimum [°C] Temperature Stability Maximum [°C] Comment Organism
3.2.1.23 22
-
 stable in 3 M NaCl for several days at room temperature Haloferax lucentense
3.2.1.38 22
-
 stable in 3 M NaCl for several days at room temperature Haloferax lucentense

pH Optimum

EC Number pH Optimum Minimum pH Optimum Maximum Comment Organism
3.2.1.23 7.2
-
 assay at Haloferax lucentense
3.2.1.38 7.2
-
 assay at Haloferax lucentense