ID   NIA_CHLVU               Reviewed;         318 AA.
AC   Q01170;
DT   01-APR-1993, integrated into UniProtKB/Swiss-Prot.
DT   01-APR-1993, sequence version 1.
DT   03-AUG-2022, entry version 96.
DE   RecName: Full=Nitrate reductase [NADH];
DE            Short=NR;
DE            EC=1.7.1.1;
DE   Flags: Fragment;
OS   Chlorella vulgaris (Green alga).
OC   Eukaryota; Viridiplantae; Chlorophyta; core chlorophytes; Trebouxiophyceae;
OC   Chlorellales; Chlorellaceae; Chlorella clade; Chlorella.
OX   NCBI_TaxID=3077;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RX   PubMed=1883330; DOI=10.1042/bj2780203;
RA   Cannons A.C., Iida N., Solomonson L.P.;
RT   "Expression of a cDNA clone encoding the haem-binding domain of Chlorella
RT   nitrate reductase.";
RL   Biochem. J. 278:203-209(1991).
CC   -!- FUNCTION: Nitrate reductase is a key enzyme involved in the first step
CC       of nitrate assimilation in plants, fungi and bacteria.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=H2O + NAD(+) + nitrite = H(+) + NADH + nitrate;
CC         Xref=Rhea:RHEA:17913, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378,
CC         ChEBI:CHEBI:16301, ChEBI:CHEBI:17632, ChEBI:CHEBI:57540,
CC         ChEBI:CHEBI:57945; EC=1.7.1.1;
CC   -!- COFACTOR:
CC       Name=FAD; Xref=ChEBI:CHEBI:57692; Evidence={ECO:0000250};
CC       Note=Binds 1 FAD per subunit. {ECO:0000250};
CC   -!- COFACTOR:
CC       Name=heme; Xref=ChEBI:CHEBI:30413; Evidence={ECO:0000250};
CC       Note=Binds 1 heme group per subunit. {ECO:0000250};
CC   -!- COFACTOR:
CC       Name=Mo-molybdopterin; Xref=ChEBI:CHEBI:71302; Evidence={ECO:0000250};
CC       Note=Binds 1 Mo-molybdopterin (Mo-MPT) cofactor per subunit.
CC       {ECO:0000250};
CC   -!- SUBUNIT: Homodimer.
CC   -!- SIMILARITY: Belongs to the nitrate reductase family. {ECO:0000305}.
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DR   EMBL; X56771; CAA40090.1; -; mRNA.
DR   PIR; S17197; S17197.
DR   AlphaFoldDB; Q01170; -.
DR   SMR; Q01170; -.
DR   GO; GO:0020037; F:heme binding; IEA:InterPro.
DR   GO; GO:0030151; F:molybdenum ion binding; IEA:InterPro.
DR   GO; GO:0009703; F:nitrate reductase (NADH) activity; IEA:UniProtKB-EC.
DR   GO; GO:0042128; P:nitrate assimilation; IEA:UniProtKB-KW.
DR   Gene3D; 3.10.120.10; -; 1.
DR   InterPro; IPR001834; CBR-like.
DR   InterPro; IPR001199; Cyt_B5-like_heme/steroid-bd.
DR   InterPro; IPR036400; Cyt_B5-like_heme/steroid_sf.
DR   InterPro; IPR018506; Cyt_B5_heme-BS.
DR   InterPro; IPR014756; Ig_E-set.
DR   InterPro; IPR005066; MoCF_OxRdtse_dimer.
DR   InterPro; IPR008335; Mopterin_OxRdtase_euk.
DR   PANTHER; PTHR19370; PTHR19370; 1.
DR   Pfam; PF00173; Cyt-b5; 1.
DR   Pfam; PF03404; Mo-co_dimer; 1.
DR   PRINTS; PR00363; CYTOCHROMEB5.
DR   PRINTS; PR00407; EUMOPTERIN.
DR   SMART; SM01117; Cyt-b5; 1.
DR   SUPFAM; SSF55856; SSF55856; 1.
DR   SUPFAM; SSF81296; SSF81296; 1.
DR   PROSITE; PS00191; CYTOCHROME_B5_1; 1.
DR   PROSITE; PS50255; CYTOCHROME_B5_2; 1.
PE   2: Evidence at transcript level;
KW   FAD; Flavoprotein; Heme; Iron; Metal-binding; Molybdenum; NAD;
KW   Nitrate assimilation; Oxidoreductase.
FT   CHAIN           <1..>318
FT                   /note="Nitrate reductase [NADH]"
FT                   /id="PRO_0000166053"
FT   DOMAIN          216..291
FT                   /note="Cytochrome b5 heme-binding"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00279"
FT   BINDING         251
FT                   /ligand="heme"
FT                   /ligand_id="ChEBI:CHEBI:30413"
FT                   /ligand_part="Fe"
FT                   /ligand_part_id="ChEBI:CHEBI:18248"
FT                   /note="axial binding residue"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00279"
FT   BINDING         274
FT                   /ligand="heme"
FT                   /ligand_id="ChEBI:CHEBI:30413"
FT                   /ligand_part="Fe"
FT                   /ligand_part_id="ChEBI:CHEBI:18248"
FT                   /note="axial binding residue"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00279"
FT   NON_TER         1
FT   NON_TER         318
SQ   SEQUENCE   318 AA;  34830 MW;  E60D82FE1E98292A CRC64;
     RPPVTEVESQ NYYHFHDNRV LPSHVDEALA NSEGWWYKPD FIINDLNVQS AIGYPAHEEV
     VPLVAGTYAV RGYARGHGNK IIRCEVSLDD GKSWRLGSVT HEGQPTEYGK HWGWVWWSLE
     VPIAELLTTP EIICRAWDSS MNTQPNTFTW NVMGMMNNCC YRVKIHPRQT TDGRFALQFE
     HPTIAGPTVG GWMNRAEDVA AAAAVTVAPP PAPAGAKSFT MAEVETHTTM ESAWFVVDGK
     VYDATPFLKD HPGGADSILL VAGIDATDEF NAIHSLKAKK QLLEYYIGEL AEEGQEAAAS
     DRATPGPAAA IGTAVPVA