BCHB_HELMO
ID BCHB_HELMO Reviewed; 520 AA.
AC Q9ZGE8;
DT 27-APR-2001, integrated into UniProtKB/Swiss-Prot.
DT 27-APR-2001, sequence version 2.
DT 03-AUG-2022, entry version 74.
DE RecName: Full=Light-independent protochlorophyllide reductase subunit B {ECO:0000255|HAMAP-Rule:MF_00353};
DE Short=DPOR subunit B {ECO:0000255|HAMAP-Rule:MF_00353};
DE Short=LI-POR subunit B {ECO:0000255|HAMAP-Rule:MF_00353};
DE EC=1.3.7.7 {ECO:0000255|HAMAP-Rule:MF_00353};
GN Name=bchB {ECO:0000255|HAMAP-Rule:MF_00353};
OS Heliobacterium mobile (Heliobacillus mobilis).
OC Bacteria; Firmicutes; Clostridia; Eubacteriales; Heliobacteriaceae;
OC Heliobacterium.
OX NCBI_TaxID=28064;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RX PubMed=9843979; DOI=10.1073/pnas.95.25.14851;
RA Xiong J., Inoue K., Bauer C.E.;
RT "Tracking molecular evolution of photosynthesis by characterization of a
RT major photosynthesis gene cluster from Heliobacillus mobilis.";
RL Proc. Natl. Acad. Sci. U.S.A. 95:14851-14856(1998).
CC -!- FUNCTION: Component of the dark-operative protochlorophyllide reductase
CC (DPOR) that uses Mg-ATP and reduced ferredoxin to reduce ring D of
CC protochlorophyllide (Pchlide) to form chlorophyllide a (Chlide). This
CC reaction is light-independent. The NB-protein (BchN-BchB) is the
CC catalytic component of the complex. {ECO:0000255|HAMAP-Rule:MF_00353}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=2 ADP + chlorophyllide a + oxidized 2[4Fe-4S]-[ferredoxin] + 2
CC phosphate = 2 ATP + 2 H2O + protochlorophyllide a + reduced 2[4Fe-
CC 4S]-[ferredoxin]; Xref=Rhea:RHEA:28202, Rhea:RHEA-COMP:10002,
CC Rhea:RHEA-COMP:10004, ChEBI:CHEBI:15377, ChEBI:CHEBI:30616,
CC ChEBI:CHEBI:33722, ChEBI:CHEBI:33723, ChEBI:CHEBI:43474,
CC ChEBI:CHEBI:83348, ChEBI:CHEBI:83350, ChEBI:CHEBI:456216; EC=1.3.7.7;
CC Evidence={ECO:0000255|HAMAP-Rule:MF_00353};
CC -!- COFACTOR:
CC Name=[4Fe-4S] cluster; Xref=ChEBI:CHEBI:49883;
CC Evidence={ECO:0000255|HAMAP-Rule:MF_00353};
CC Note=Binds 1 [4Fe-4S] cluster per heterodimer. The cluster is bound at
CC the heterodimer interface by residues from both subunits.
CC {ECO:0000255|HAMAP-Rule:MF_00353};
CC -!- PATHWAY: Porphyrin-containing compound metabolism; bacteriochlorophyll
CC biosynthesis (light-independent). {ECO:0000255|HAMAP-Rule:MF_00353}.
CC -!- SUBUNIT: Protochlorophyllide reductase is composed of three subunits;
CC BchL, BchN and BchB. Forms a heterotetramer of two BchB and two BchN
CC subunits. {ECO:0000255|HAMAP-Rule:MF_00353}.
CC -!- SIMILARITY: Belongs to the ChlB/BchB/BchZ family. {ECO:0000255|HAMAP-
CC Rule:MF_00353}.
CC -!- SEQUENCE CAUTION:
CC Sequence=AAC84030.1; Type=Erroneous initiation; Evidence={ECO:0000305};
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DR EMBL; AF080002; AAC84030.1; ALT_INIT; Genomic_DNA.
DR PIR; T31459; T31459.
DR AlphaFoldDB; Q9ZGE8; -.
DR SMR; Q9ZGE8; -.
DR UniPathway; UPA00671; -.
DR GO; GO:0051539; F:4 iron, 4 sulfur cluster binding; IEA:UniProtKB-UniRule.
DR GO; GO:0005524; F:ATP binding; IEA:UniProtKB-UniRule.
DR GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
DR GO; GO:0016730; F:oxidoreductase activity, acting on iron-sulfur proteins as donors; IEA:InterPro.
DR GO; GO:0016636; F:oxidoreductase activity, acting on the CH-CH group of donors, iron-sulfur protein as acceptor; IEA:UniProtKB-UniRule.
DR GO; GO:0036070; P:light-independent bacteriochlorophyll biosynthetic process; IEA:UniProtKB-UniPathway.
DR GO; GO:0019685; P:photosynthesis, dark reaction; IEA:InterPro.
DR Gene3D; 1.10.8.550; -; 1.
DR HAMAP; MF_00353; ChlB_BchB; 1.
DR InterPro; IPR013580; LI-POR_suB-like_C.
DR InterPro; IPR000510; Nase/OxRdtase_comp1.
DR InterPro; IPR042298; P-CP_red_C.
DR InterPro; IPR005969; Protochl_reductB.
DR InterPro; IPR016209; Protochlorophyllide_Rdtase.
DR Pfam; PF00148; Oxidored_nitro; 1.
DR Pfam; PF08369; PCP_red; 1.
DR PIRSF; PIRSF000163; PCP_ChlB; 1.
DR TIGRFAMs; TIGR01278; DPOR_BchB; 1.
PE 3: Inferred from homology;
KW 4Fe-4S; ATP-binding; Bacteriochlorophyll biosynthesis;
KW Chlorophyll biosynthesis; Iron; Iron-sulfur; Metal-binding;
KW Nucleotide-binding; Oxidoreductase; Photosynthesis.
FT CHAIN 1..520
FT /note="Light-independent protochlorophyllide reductase
FT subunit B"
FT /id="PRO_0000219799"
FT REGION 429..457
FT /note="Disordered"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT ACT_SITE 281
FT /note="Proton donor"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00353"
FT BINDING 36
FT /ligand="[4Fe-4S] cluster"
FT /ligand_id="ChEBI:CHEBI:49883"
FT /ligand_note="ligand shared with heterodimeric partner"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00353"
FT BINDING 416..417
FT /ligand="substrate"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00353"
SQ SEQUENCE 520 AA; 57775 MW; 7A2AC5F4AEC8A4BD CRC64;
MKLAYWMYEG TALSGITRVA GSMQKVHTVI HGPQGDGYVN VMYSMLERFH TIPPFTLSTI
GRREMAQGSR ARLVETVRRV DAQHQPDVIV ITPTCSSTLL QEDLLAVART LGKQTKAKLI
VPNVNAFRDL EHRAMDDFLT QIVAEFATEQ PKTEQFSVNL IGPSYLGFHQ LHDMQEIRSM
LESLGVAVNA VIPYGASIKT LQELTKAHLN ICLYHEYGQS ACELLKEKFG IDYIVATPIG
IRLTSQFVKA IGERAGLPVE SYIRQNLAPS GTIARFTKSV DSLSALFGKR AVVFGDYSHA
VGMTHLLREI GVRVVWAGTY MKTMEKAFQA SIGGLADEVF VCDDFQEISH KIRDTHPDIV
LGTQMERHSA ARFNFPCIVI SSPAHILNFP LFPAPVLGYQ GMTRMLDTIN STIKLGLEEH
LVNMFGEDSP GMGEEDTAQE QVAVTSDMPK APDKTTAGEG ELKWDAEATK ALKQVPFFVR
GKVQRNTENY ARERGYSEVT LEVIYAAKAY FESKSNQGER
