AC   MF_01687;
DC   Protein; auto
TR   HAMAP; MF_01687; -; 1; level=0
XX
Names: Beta_gal
XX
ID   BGAL
DE   RecName: Full=Beta-galactosidase;
DE            Short=Beta-gal;
DE            EC=3.2.1.23;
DE   AltName: Full=Lactase;
GN   Name=lacZ;
XX
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=Hydrolysis of terminal non-reducing beta-D-galactose residues
CC         in beta-D-galactosides.; EC=3.2.1.23;
CC   -!- COFACTOR:
CC       Name=Mg(2+); Xref=ChEBI:CHEBI:18420;
CC       Note=Binds 2 magnesium ions per monomer.;
CC   -!- COFACTOR:
CC       Name=Na(+); Xref=ChEBI:CHEBI:29101;
CC       Note=Binds 1 sodium ion per monomer.;
CC   -!- SUBUNIT: Homotetramer.
CC   -!- SIMILARITY: Belongs to the glycosyl hydrolase 2 family.
XX
DR   PROSITE; PS00719; GLYCOSYL_HYDROL_F2_1; 1; trigger=no
DR   PROSITE; PS00608; GLYCOSYL_HYDROL_F2_2; 1; trigger=no
DR   Pfam; PF02929; Bgal_small_N; 1; trigger=no
DR   Pfam; PF00703; Glyco_hydro_2; 1; trigger=no
DR   Pfam; PF02836; Glyco_hydro_2_C; 1; trigger=no
DR   Pfam; PF02837; Glyco_hydro_2_N; 1; trigger=no
DR   PRINTS; PR00132; GLHYDRLASE2; 1; trigger=no
XX
KW   Glycosidase
KW   Hydrolase
KW   Magnesium
KW   Metal-binding
KW   Sodium
XX
GO   GO:0000287; F:magnesium ion binding
GO   GO:0016798; F:hydrolase activity, acting on glycosyl bonds
XX
FT   From: BGAL_ECOLI (P00722)
FT   BINDING         538..541
FT                   /ligand="substrate"
FT   Condition: E-Y-A-H
FT   ACT_SITE        462
FT                   /note="Proton donor"
FT   Condition: E
FT   ACT_SITE        538
FT                   /note="Nucleophile"
FT   Condition: E
FT   BINDING         202
FT                   /ligand="Na(+)"
FT                   /ligand_id="ChEBI:CHEBI:29101"
FT   Condition: D
FT   BINDING         417
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /ligand_label="1"
FT   Condition: E
FT   BINDING         419
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /ligand_label="1"
FT   Condition: H
FT   BINDING         462
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /ligand_label="1"
FT   Condition: E
FT   BINDING         598
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /ligand_label="2"
FT   Condition: N
FT   BINDING         602
FT                   /ligand="Na(+)"
FT                   /ligand_id="ChEBI:CHEBI:29101"
FT   Condition: F
FT   BINDING         605
FT                   /ligand="Na(+)"
FT                   /ligand_id="ChEBI:CHEBI:29101"
FT   Condition: [DN]
FT   BINDING         103
FT                   /ligand="substrate"
FT   Condition: N
FT   BINDING         202
FT                   /ligand="substrate"
FT   Condition: D
FT   BINDING         462
FT                   /ligand="substrate"
FT   Condition: E
FT   BINDING         605
FT                   /ligand="substrate"
FT   Condition: [DN]
FT   BINDING         1000
FT                   /ligand="substrate"
FT   Condition: W
FT   SITE            358
FT                   /note="Transition state stabilizer"
FT   Condition: H
FT   SITE            392
FT                   /note="Transition state stabilizer"
FT   Condition: H
XX
Size: 1020-1066;
Related: None;
Template: P00722; A3FEW8; P81650;
Scope:
 Bacteria
Fusion:
 Nter: None
 Cter: None
Duplicate: in ENTCL, KLEP7, KLEPN
Plasmid: in ECOLX, KLEP7, KLEPN
Comments: ENTAG, and maybe other bacteria, are able to transfer a glycosyl
 to the hydroxyl groups of a series of accecptors including hexose, pentose,
 disaccharides, hexahydroxy alcohol, cyclitol, and aromatic glycosides.
XX
# Revision 1.13 2022/11/19
//