ID   LDHB_PELSJ              Reviewed;         333 AA.
AC   Q98SK9;
DT   16-NOV-2001, integrated into UniProtKB/Swiss-Prot.
DT   23-JAN-2007, sequence version 3.
DT   03-AUG-2022, entry version 104.
DE   RecName: Full=L-lactate dehydrogenase B chain;
DE            Short=LDH-B;
DE            EC=1.1.1.27 {ECO:0000250|UniProtKB:P07195};
GN   Name=LDHB;
OS   Pelodiscus sinensis japonicus (Chinese soft-shelled turtle).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
OC   Archelosauria; Testudinata; Testudines; Cryptodira; Trionychia;
OC   Trionychidae; Pelodiscus.
OX   NCBI_TaxID=34908;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RC   TISSUE=Heart;
RX   PubMed=11722846; DOI=10.1016/s0378-1119(01)00746-6;
RA   Liao C.-H., Ho W.-Z., Huang H.-W., Kuo C.-H., Lee S.-C., Li S.S.-L.;
RT   "Lactate dehydrogenase genes of caiman and Chinese soft-shelled turtle,
RT   with emphasis on the molecular phylogenetics and evolution of reptiles.";
RL   Gene 279:63-67(2001).
CC   -!- FUNCTION: Interconverts simultaneously and stereospecifically pyruvate
CC       and lactate with concomitant interconversion of NADH and NAD(+).
CC       {ECO:0000250|UniProtKB:P07195}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=(S)-lactate + NAD(+) = H(+) + NADH + pyruvate;
CC         Xref=Rhea:RHEA:23444, ChEBI:CHEBI:15361, ChEBI:CHEBI:15378,
CC         ChEBI:CHEBI:16651, ChEBI:CHEBI:57540, ChEBI:CHEBI:57945; EC=1.1.1.27;
CC         Evidence={ECO:0000250|UniProtKB:P07195};
CC       PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:23445;
CC         Evidence={ECO:0000250|UniProtKB:P07195};
CC       PhysiologicalDirection=right-to-left; Xref=Rhea:RHEA:23446;
CC         Evidence={ECO:0000250|UniProtKB:P07195};
CC   -!- PATHWAY: Fermentation; pyruvate fermentation to lactate; (S)-lactate
CC       from pyruvate: step 1/1. {ECO:0000250|UniProtKB:P07195}.
CC   -!- SUBUNIT: Homotetramer. {ECO:0000250}.
CC   -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000250}.
CC   -!- SIMILARITY: Belongs to the LDH/MDH superfamily. LDH family.
CC       {ECO:0000305}.
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; AF363795; AAK37573.1; -; mRNA.
DR   AlphaFoldDB; Q98SK9; -.
DR   SMR; Q98SK9; -.
DR   UniPathway; UPA00554; UER00611.
DR   GO; GO:0005737; C:cytoplasm; IEA:UniProtKB-SubCell.
DR   GO; GO:0004459; F:L-lactate dehydrogenase activity; IEA:UniProtKB-EC.
DR   GO; GO:0019752; P:carboxylic acid metabolic process; IEA:InterPro.
DR   Gene3D; 3.90.110.10; -; 1.
DR   HAMAP; MF_00488; Lactate_dehydrog; 1.
DR   InterPro; IPR001557; L-lactate/malate_DH.
DR   InterPro; IPR011304; L-lactate_DH.
DR   InterPro; IPR018177; L-lactate_DH_AS.
DR   InterPro; IPR022383; Lactate/malate_DH_C.
DR   InterPro; IPR001236; Lactate/malate_DH_N.
DR   InterPro; IPR015955; Lactate_DH/Glyco_Ohase_4_C.
DR   InterPro; IPR036291; NAD(P)-bd_dom_sf.
DR   Pfam; PF02866; Ldh_1_C; 1.
DR   Pfam; PF00056; Ldh_1_N; 1.
DR   PIRSF; PIRSF000102; Lac_mal_DH; 1.
DR   PRINTS; PR00086; LLDHDRGNASE.
DR   SUPFAM; SSF51735; SSF51735; 1.
DR   SUPFAM; SSF56327; SSF56327; 1.
DR   TIGRFAMs; TIGR01771; L-LDH-NAD; 1.
DR   PROSITE; PS00064; L_LDH; 1.
PE   2: Evidence at transcript level;
KW   Cytoplasm; NAD; Oxidoreductase.
FT   INIT_MET        1
FT                   /note="Removed"
FT                   /evidence="ECO:0000250"
FT   CHAIN           2..333
FT                   /note="L-lactate dehydrogenase B chain"
FT                   /id="PRO_0000168470"
FT   ACT_SITE        193
FT                   /note="Proton acceptor"
FT                   /evidence="ECO:0000250"
FT   BINDING         29..57
FT                   /ligand="NAD(+)"
FT                   /ligand_id="ChEBI:CHEBI:57540"
FT                   /evidence="ECO:0000250"
FT   BINDING         99
FT                   /ligand="NAD(+)"
FT                   /ligand_id="ChEBI:CHEBI:57540"
FT                   /evidence="ECO:0000250"
FT   BINDING         106
FT                   /ligand="substrate"
FT                   /evidence="ECO:0000250"
FT   BINDING         138
FT                   /ligand="NAD(+)"
FT                   /ligand_id="ChEBI:CHEBI:57540"
FT                   /evidence="ECO:0000250"
FT   BINDING         138
FT                   /ligand="substrate"
FT                   /evidence="ECO:0000250"
FT   BINDING         169
FT                   /ligand="substrate"
FT                   /evidence="ECO:0000250"
FT   BINDING         248
FT                   /ligand="substrate"
FT                   /evidence="ECO:0000250"
SQ   SEQUENCE   333 AA;  36403 MW;  1CF95FD6523EF343 CRC64;
     MATLQEKLIT PIVAGSTTPN NKITVVGVGQ VGMACAISIL GKGLCDELAL VDVLEDKLKG
     EMMDLQHGSL FLQTHKIVAD KDLRVTANSK IVVVTAGVRQ QEGESRLNLV QRNVNVFKFI
     IPQIMKYSPN CTILVVSNPV DILTYVTWKL SGLPKHRVIG SGCNLDSARF RHLMAEKLGI
     HPTSCHGWIL GEHGDSSVAV WSGVNVAGVS LQELNPAMGT DKDSENWKEV HKMVVDSAYE
     VIKLKGYTNW AIGLSVADLI ESYVKNLCRV HPVSTMVKGM YGIENEVFLS LPCVLSASGL
     TSVINQKLKD EEVAQLRKSA DTLWSIQKDL KDL