A1A399 · BGAL_BIFAA
- ProteinBeta-galactosidase BgaB
- GenebgaB
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids700 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Involved in the hydrolysis of transgalactooligosaccharides (TOS). Highly active towards Gal(beta1-4)Gal and Gal(beta1-4)-Gal-containing oligosaccharides. Low activity towards Gal(beta1-3)Gal, lactose and Gal(beta1-3)GalOMe. No activity towards Gal(beta1-6)Gal, Gal(beta1-4)Man, Gal(alpha1-4)Gal, Gal(alpha1-3)Gal(beta1-4)Gal, lactulose, 3'fucosyllactose, lacto-N-fucopentaose I, lacto-N-fucopentaose II, cellobiose, maltose or sucrose. No transglycosylation activity is found at high substrate concentrations (100 mg/ml) and only low transglycosylation activity at lower substrate concentrations (10 mg/ml).
Catalytic activity
Activity regulation
Inhibited by high substrate concentrations (100 mg/ml). No effect on activity with various EDTA concentrations (0-1 mM). 20-fold higher activity when cells grown on TOS than when cells grown on galactose, glucose and lactose.
Kinetics
KM | SUBSTRATE | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|---|
60 mM | Gal(beta1-4)Gal | 6.0 | 37 | |||
2.2 mM | p-nitrophenyl-beta-D-galactopyranoside (PNPG) | 6.0 | 40 | |||
2.2 mM | beta-D-Galp-(1->4)-beta-D-Galp-(1->4)-D-Glcp | 6.0 | 40 | |||
4 mM | beta-D-Galp-(1->4)-beta-D-Galp-(1->4)-beta-D-Galp-(1->4)-D-Glcp | 6.0 | 40 | |||
3.7 mM | beta-D-Galp-(1->4)-D-Galp | 6.0 | 40 | |||
6.4 mM | beta-D-Galp-(1->4)-beta-D-Galp-(1->4)-D-Galp | 6.0 | 40 | |||
5.2 mM | beta-D-Galp-(1->4)-beta-D-Galp-(1->4)-beta-D-Galp-(1->4)-D-Galp | 6.0 | 40 |
Vmax | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|
1.129 μmol/min/mg | 6.0 | 37 | with Gal(beta1-4)Gal as substrate |
pH Dependence
Optimum is pH 6.0 using PNPG or TOS as substrate. Not active below pH 5.
Temperature Dependence
Optimum temperature is 50 degrees Celsius using PNPG as substrate (PubMed:15480628).
Optimum temperature is 35 degrees Celsius using TOS as substrate (PubMed:10742215).
Stable at 40 degrees Celsius. Half-life time at 50 degrees Celsius is 10 minutes.
Optimum temperature is 35 degrees Celsius using TOS as substrate (PubMed:10742215).
Stable at 40 degrees Celsius. Half-life time at 50 degrees Celsius is 10 minutes.
Features
Showing features for binding site, active site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 122 | substrate | ||||
Sequence: R | ||||||
Binding site | 160 | substrate | ||||
Sequence: N | ||||||
Active site | 161 | Proton donor | ||||
Sequence: E | ||||||
Active site | 320 | Nucleophile | ||||
Sequence: E | ||||||
Binding site | 328 | substrate | ||||
Sequence: W | ||||||
Binding site | 368-371 | substrate | ||||
Sequence: EAFH |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | beta-galactosidase complex | |
Molecular Function | beta-galactosidase activity | |
Biological Process | carbohydrate metabolic process |
Keywords
- Molecular function
Enzyme and pathway databases
Protein family/group databases
Names & Taxonomy
Protein names
- Recommended nameBeta-galactosidase BgaB
- EC number
- Short namesBeta-gal
- Alternative names
Gene names
Organism names
- Strain
- Taxonomic lineageBacteria > Actinomycetota > Actinomycetes > Bifidobacteriales > Bifidobacteriaceae > Bifidobacterium
Accessions
- Primary accessionA1A399
- Secondary accessions
Proteomes
Subcellular Location
UniProt Annotation
GO Annotation
PTM/Processing
Features
Showing features for initiator methionine, chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Initiator methionine | 1 | Removed | ||||
Sequence: M | ||||||
Chain | PRO_0000407683 | 2-700 | Beta-galactosidase BgaB | |||
Sequence: SARRNFEWPELLTADGRGIAFGGDYNPDQWSEDIWDDDIRLMKQAGVNTVALAIFSWDRIQPTEDRWDFGWLDRIIDKLGNAGIVVDLASATATAPLWLYESHPEVLPRDKYGHPVNAGSRQSWSPTSPVFKEYALTLCRKLAERYGTNPYVTAWHMGNEYGWNNREDYSDNALEAFRAWCRRKYGTIDALNQAWGTTFWGQEMNGFDEVLIPRFMGADSMVNPGQKLDFERFGNDMLLDFYKAERDAIAEICPDKPFTTNFMVSTDQCCMDYAAWAKEVNFVSNDHYFHEGESHLDELACSDALMDSLALGKPWYVMEHSTSAVQWKPLNTRKRKGETVRDSLAHVAMGADAINFFQWRASAFGAEAFHSAMVPHAGEDTKLFRQVCELGASLHTLADAGVQGTELAHSDTAILFSAESEWATRSQTLPSMKLNHWHDVRDWYRAFLDAGSRADIVPLAYDWSSYKTVVLPTVLILSAADTQRLADFAAAGGRVVVGYATGLIDEHFHTWLGGYPGAGDGLLRSMLGVRGEEFNILGAEAEGEPGEIRLSSADDSAALDGTTTRLWQNDVNVTGEHAQVLATYAGEEADEWELDGTAAVTRNPYGSGEAYFVGCDLDVADLTKLVRAYLAASSQENADVLHTVRASADATFDFYLPRGKKTVELQGIEGEPVILFQTDREEKPGSYTVRRNGVLVVRR |
Post-translational modification
The N-terminus is blocked.
Proteomic databases
Structure
Sequence
- Sequence statusComplete
- Length700
- Mass (Da)78,025
- Last updated2011-05-03 v2
- Checksum9EDB064761188A52
Sequence caution
Features
Showing features for sequence conflict.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Sequence conflict | 213-230 | in Ref. 1; AAR24113 | ||||
Sequence: IPRFMGADSMVNPGQKLD → HPTVHGRRLRWSTPARSST | ||||||
Sequence conflict | 536 | in Ref. 1; AAR24113 | ||||
Sequence: N → T |
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
AY359872 EMBL· GenBank· DDBJ | AAR24113.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
AP009256 EMBL· GenBank· DDBJ | BAF40182.1 EMBL· GenBank· DDBJ | Genomic DNA | Different initiation |