ID   DKGB_CORSS              Reviewed;         277 AA.
AC   P15339;
DT   01-APR-1990, integrated into UniProtKB/Swiss-Prot.
DT   23-JAN-2007, sequence version 3.
DT   03-AUG-2022, entry version 93.
DE   RecName: Full=2,5-diketo-D-gluconic acid reductase B;
DE            Short=2,5-DKG reductase B;
DE            Short=2,5-DKGR B;
DE            Short=25DKGR-B;
DE            EC=1.1.1.274;
DE   AltName: Full=AKR5D;
GN   Name=dkgB;
OS   Corynebacterium sp. (strain SHS752001).
OC   Bacteria; Actinobacteria; Corynebacteriales; Corynebacteriaceae;
OC   Corynebacterium; unclassified Corynebacterium.
OX   NCBI_TaxID=268953;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA], PROTEIN SEQUENCE OF 2-61 AND 147-176,
RP   AND FUNCTION.
RX   PubMed=16347687; DOI=10.1128/aem.54.7.1770-1775.1988;
RA   Grindley J.F., Payton M.A., van de Pol H., Hardy K.G.;
RT   "Conversion of glucose to 2-keto-L-gulonate, an intermediate in L-ascorbate
RT   synthesis, by a recombinant strain of Erwinia citreus.";
RL   Appl. Environ. Microbiol. 54:1770-1775(1988).
CC   -!- FUNCTION: Catalyzes the reduction of 2,5-diketo-D-gluconic acid (25DKG)
CC       to 2-keto-L-gulonic acid (2KLG). 25DKGR-B has higher catalytic
CC       efficiency than 25DKGR-A. {ECO:0000269|PubMed:16347687}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=2-dehydro-D-gluconate + NADP(+) = 2,5-didehydro-D-gluconate +
CC         H(+) + NADPH; Xref=Rhea:RHEA:23828, ChEBI:CHEBI:11449,
CC         ChEBI:CHEBI:15378, ChEBI:CHEBI:16808, ChEBI:CHEBI:57783,
CC         ChEBI:CHEBI:58349; EC=1.1.1.274;
CC   -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000305}.
CC   -!- MISCELLANEOUS: 2-keto-L-gulonic acid is a key intermediate in the
CC       production of L-ascorbic acid (vitamin C).
CC   -!- SIMILARITY: Belongs to the aldo/keto reductase family. {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; M21193; AAA23291.1; -; Genomic_DNA.
DR   PIR; A45961; A45961.
DR   AlphaFoldDB; P15339; -.
DR   SMR; P15339; -.
DR   GO; GO:0005737; C:cytoplasm; IEA:UniProtKB-SubCell.
DR   GO; GO:0050580; F:2,5-didehydrogluconate reductase activity; IEA:UniProtKB-EC.
DR   GO; GO:0019853; P:L-ascorbic acid biosynthetic process; IEA:UniProtKB-KW.
DR   Gene3D; 3.20.20.100; -; 1.
DR   InterPro; IPR020471; AKR.
DR   InterPro; IPR018170; Aldo/ket_reductase_CS.
DR   InterPro; IPR023210; NADP_OxRdtase_dom.
DR   InterPro; IPR036812; NADP_OxRdtase_dom_sf.
DR   PANTHER; PTHR43827; PTHR43827; 1.
DR   Pfam; PF00248; Aldo_ket_red; 1.
DR   PIRSF; PIRSF000097; AKR; 1.
DR   PRINTS; PR00069; ALDKETRDTASE.
DR   SUPFAM; SSF51430; SSF51430; 1.
DR   PROSITE; PS00798; ALDOKETO_REDUCTASE_1; 1.
DR   PROSITE; PS00062; ALDOKETO_REDUCTASE_2; 1.
DR   PROSITE; PS00063; ALDOKETO_REDUCTASE_3; 1.
PE   1: Evidence at protein level;
KW   Ascorbate biosynthesis; Cytoplasm; Direct protein sequencing; NADP;
KW   Oxidoreductase.
FT   INIT_MET        1
FT                   /note="Removed"
FT                   /evidence="ECO:0000269|PubMed:16347687"
FT   CHAIN           2..277
FT                   /note="2,5-diketo-D-gluconic acid reductase B"
FT                   /id="PRO_0000124598"
FT   ACT_SITE        51
FT                   /note="Proton donor"
FT                   /evidence="ECO:0000250"
FT   BINDING         109
FT                   /ligand="substrate"
FT                   /evidence="ECO:0000250"
FT   BINDING         189..242
FT                   /ligand="NADP(+)"
FT                   /ligand_id="ChEBI:CHEBI:58349"
FT                   /evidence="ECO:0000250"
SQ   SEQUENCE   277 AA;  30548 MW;  7E72D1C24FFD30AA CRC64;
     MPNIPTISLN DGRPFAEPGL GTYNLRGDEG VAAMVAAIDS GYRLLDTAVN YENESEVGRA
     VRASSVDRDE LIVASKIPGR QHGRAEAVDS IRGSLDRLGL DVIDLQLIHW PNPSVGRWLD
     TWRGMIDARE AGLVRSIGVS NFTEPMLKTL IDETGVTPAV NQVELHPYFP QAALRAFHDE
     HGIRTESWSP LARRSELLTE QLLQELAVVY GVTPTQVVLR WHVQLGSTPI PKSADPDRQR
     ENADVFGFAL TADQVDAISG LERGRLWDGD PDTHEEM