ID BGAL2_ENTCL Reviewed; 1029 AA. AC Q2XQU3; DT 24-MAR-2009, integrated into UniProtKB/Swiss-Prot. DT 20-DEC-2005, sequence version 1. DT 27-MAR-2024, entry version 66. DE RecName: Full=Beta-galactosidase 2 {ECO:0000255|HAMAP-Rule:MF_01687}; DE Short=Beta-gal {ECO:0000255|HAMAP-Rule:MF_01687}; DE EC=3.2.1.23 {ECO:0000255|HAMAP-Rule:MF_01687}; DE AltName: Full=Lactase {ECO:0000255|HAMAP-Rule:MF_01687}; GN Name=lacZ {ECO:0000255|HAMAP-Rule:MF_01687}; Synonyms=bga; OS Enterobacter cloacae. OC Bacteria; Pseudomonadota; Gammaproteobacteria; Enterobacterales; OC Enterobacteriaceae; Enterobacter; Enterobacter cloacae complex. OX NCBI_TaxID=550; RN [1] RP NUCLEOTIDE SEQUENCE [GENOMIC DNA]. RC STRAIN=B5; RA Lu L.L., Xiao M.; RT "Purification, characterization, and molecular cloning of a beta- RT galactosidase with transglycosylation activity from Enterobacter cloacae."; RL Submitted (OCT-2005) to the EMBL/GenBank/DDBJ databases. CC -!- CATALYTIC ACTIVITY: CC Reaction=Hydrolysis of terminal non-reducing beta-D-galactose residues CC in beta-D-galactosides.; EC=3.2.1.23; Evidence={ECO:0000255|HAMAP- CC Rule:MF_01687}; CC -!- COFACTOR: CC Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000255|HAMAP- CC Rule:MF_01687}; CC Note=Binds 2 magnesium ions per monomer. {ECO:0000255|HAMAP- CC Rule:MF_01687}; CC -!- COFACTOR: CC Name=Na(+); Xref=ChEBI:CHEBI:29101; Evidence={ECO:0000255|HAMAP- CC Rule:MF_01687}; CC Note=Binds 1 sodium ion per monomer. {ECO:0000255|HAMAP-Rule:MF_01687}; CC -!- SUBUNIT: Homotetramer. {ECO:0000255|HAMAP-Rule:MF_01687}. CC -!- SIMILARITY: Belongs to the glycosyl hydrolase 2 family. CC {ECO:0000255|HAMAP-Rule:MF_01687}. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR EMBL; DQ266449; ABB73039.1; -; Genomic_DNA. DR AlphaFoldDB; Q2XQU3; -. DR SMR; Q2XQU3; -. DR CAZy; GH2; Glycoside Hydrolase Family 2. DR GO; GO:0009341; C:beta-galactosidase complex; IEA:InterPro. DR GO; GO:0004565; F:beta-galactosidase activity; IEA:UniProtKB-EC. DR GO; GO:0030246; F:carbohydrate binding; IEA:InterPro. DR GO; GO:0000287; F:magnesium ion binding; IEA:UniProtKB-UniRule. DR GO; GO:0005975; P:carbohydrate metabolic process; IEA:InterPro. DR GO; GO:1901575; P:organic substance catabolic process; IEA:UniProt. DR Gene3D; 2.70.98.10; -; 1. DR Gene3D; 2.60.120.260; Galactose-binding domain-like; 1. DR Gene3D; 3.20.20.80; Glycosidases; 1. DR Gene3D; 2.60.40.10; Immunoglobulins; 2. DR HAMAP; MF_01687; Beta_gal; 1. DR InterPro; IPR004199; B-gal_small/dom_5. DR InterPro; IPR036156; Beta-gal/glucu_dom_sf. DR InterPro; IPR011013; Gal_mutarotase_sf_dom. DR InterPro; IPR008979; Galactose-bd-like_sf. DR InterPro; IPR014718; GH-type_carb-bd. DR InterPro; IPR006101; Glyco_hydro_2. DR InterPro; IPR023232; Glyco_hydro_2_AS. DR InterPro; IPR023933; Glyco_hydro_2_beta_Galsidase. DR InterPro; IPR006103; Glyco_hydro_2_cat. DR InterPro; IPR023230; Glyco_hydro_2_CS. DR InterPro; IPR006102; Glyco_hydro_2_Ig-like. DR InterPro; IPR006104; Glyco_hydro_2_N. DR InterPro; IPR017853; Glycoside_hydrolase_SF. DR InterPro; IPR013783; Ig-like_fold. DR InterPro; IPR032312; LacZ_4. DR PANTHER; PTHR46323; BETA-GALACTOSIDASE; 1. DR PANTHER; PTHR46323:SF2; BETA-GALACTOSIDASE; 1. DR Pfam; PF02929; Bgal_small_N; 1. DR Pfam; PF00703; Glyco_hydro_2; 1. DR Pfam; PF02836; Glyco_hydro_2_C; 1. DR Pfam; PF02837; Glyco_hydro_2_N; 1. DR Pfam; PF16353; LacZ_4; 1. DR PRINTS; PR00132; GLHYDRLASE2. DR SMART; SM01038; Bgal_small_N; 1. DR SUPFAM; SSF51445; (Trans)glycosidases; 1. DR SUPFAM; SSF49303; beta-Galactosidase/glucuronidase domain; 2. DR SUPFAM; SSF74650; Galactose mutarotase-like; 1. DR SUPFAM; SSF49785; Galactose-binding domain-like; 1. DR PROSITE; PS00719; GLYCOSYL_HYDROL_F2_1; 1. DR PROSITE; PS00608; GLYCOSYL_HYDROL_F2_2; 1. PE 3: Inferred from homology; KW Glycosidase; Hydrolase; Magnesium; Metal-binding; Sodium. FT CHAIN 1..1029 FT /note="Beta-galactosidase 2" FT /id="PRO_0000366983" FT ACT_SITE 463 FT /note="Proton donor" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01687" FT ACT_SITE 539 FT /note="Nucleophile" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01687" FT BINDING 104 FT /ligand="substrate" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01687" FT BINDING 203 FT /ligand="Na(+)" FT /ligand_id="ChEBI:CHEBI:29101" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01687" FT BINDING 203 FT /ligand="substrate" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01687" FT BINDING 418 FT /ligand="Mg(2+)" FT /ligand_id="ChEBI:CHEBI:18420" FT /ligand_label="1" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01687" FT BINDING 420 FT /ligand="Mg(2+)" FT /ligand_id="ChEBI:CHEBI:18420" FT /ligand_label="1" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01687" FT BINDING 463 FT /ligand="Mg(2+)" FT /ligand_id="ChEBI:CHEBI:18420" FT /ligand_label="1" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01687" FT BINDING 463 FT /ligand="substrate" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01687" FT BINDING 539..542 FT /ligand="substrate" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01687" FT BINDING 599 FT /ligand="Mg(2+)" FT /ligand_id="ChEBI:CHEBI:18420" FT /ligand_label="2" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01687" FT BINDING 603 FT /ligand="Na(+)" FT /ligand_id="ChEBI:CHEBI:29101" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01687" FT BINDING 606 FT /ligand="Na(+)" FT /ligand_id="ChEBI:CHEBI:29101" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01687" FT BINDING 606 FT /ligand="substrate" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01687" FT BINDING 1004 FT /ligand="substrate" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01687" FT SITE 393 FT /note="Transition state stabilizer" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01687" SQ SEQUENCE 1029 AA; 116816 MW; C96F1A32A29E2241 CRC64; MPNTLSLTLS AILARRDWEN PGVTQWNRLE AHAPLHSWRL EQPALDDAAS ASRRSLNGVW RFNYFPAPEQ IPEAWVTEDC ADAVPMPVPS NWQMQGFDTP IYTNVTYPIP VNPPFVPQEN PTGCYSLTFD VDDAWLQSGQ TRIIFDGVNS AFHLWCNGRW MGYSQDSRLP AEFNLSTVLR PGENRLAVMV LRWCDGSYLE DQDMWRMSGI FRDVTLLHKP ETQIADYRVV TDLNAELDRA VLKADVALAG AGFADCEVVF TLWRKGEKCA SVSRRPGSAV VDERGSWDER LTVAIPIDRP ALWSAETPEL YRLTMALLGP QGEVLEVEAC DVGFRRVDIS NGLLKLNGKP LLIRGVNRLE HHPENGQVMD EATMRRDIEI MKQHNFNAVR CSHYPNHPLW YRLCDRYGLY VVDEANIETH GMVPMSRLAD DPRWLPAMSE RVTRMVQRDR NHPSIIIWSL GNESGHGANH DALYRWLKTT DPTRPVQYEG GGANTAATDI VCPMYARVDW DQPFPAVPKW SIKKWIGMPD ETRPLILCEY AHAMGNSFGG FAKYWQAFRS HPRLQGGFVW DWVDQALTKK DEKGNAFWAY GGDFGDTPND RQFCLNGLVF PDRTPHPALY EAQRAQQFFT FTLVSTSPLM IEVQSGYLFR PTDNEVLSWT VARDGKVLAS GEVTLAIAPE GVQRLEIALP ELKAGPGEIW LNVEVRQPRA TPWSPAGHRC AWEQWPLPAP LFIAPPASTG EPPVLTQNDR ILEVTHRQQR WQFDRASGYL TQWWRNGVET LLSPVTDNVS RAPLDNDIGV SEATRIDPNA WVERWKAAGM YDLTSRMLHC EAEQHAREVV VTTLNVLEHR GRALFLSRKI WRLDEQGVLH GDIQVDIASD IPKPARIGLS VHLAETPEKV DWLGLGPHEN YPDRKLAAQQ GRWTLPLADM HTPYIFPTEN GLRCDTRKLV LGAHQLNGAF HFSVGRYSQQ QLRETTHHHL LREEPGGWLN LDAFHMGVGG DDSWSPSVSP EFILQTRQLR YTFSWQQNP //