ID   BZAA_EUBLI              Reviewed;         427 AA.
AC   A0A0K1TPY7;
DT   27-SEP-2017, integrated into UniProtKB/Swiss-Prot.
DT   11-NOV-2015, sequence version 1.
DT   25-MAY-2022, entry version 29.
DE   RecName: Full=5-hydroxybenzimidazole synthase BzaA {ECO:0000305|PubMed:26246619};
DE            Short=5-OHBza synthase {ECO:0000305|PubMed:26246619};
DE            Short=HBI synthase;
DE            EC=4.1.99.23 {ECO:0000250|UniProtKB:P61425, ECO:0000305|PubMed:26246619};
GN   Name=bzaA {ECO:0000303|PubMed:26246619, ECO:0000312|EMBL:AKV89410.1};
GN   ORFNames=SAMN04515624_11454 {ECO:0000312|EMBL:SDP52039.1};
OS   Eubacterium limosum.
OC   Bacteria; Firmicutes; Clostridia; Eubacteriales; Eubacteriaceae;
OC   Eubacterium.
OX   NCBI_TaxID=1736;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA], FUNCTION, CATALYTIC ACTIVITY, AND
RP   PATHWAY.
RC   STRAIN=ATCC 10825 / DSM 20517 / JCM 9976 / NCIMB 9554 / NCTC 10469 / 32_A2;
RX   PubMed=26246619; DOI=10.1073/pnas.1509132112;
RA   Hazra A.B., Han A.W., Mehta A.P., Mok K.C., Osadchiy V., Begley T.P.,
RA   Taga M.E.;
RT   "Anaerobic biosynthesis of the lower ligand of vitamin B12.";
RL   Proc. Natl. Acad. Sci. U.S.A. 112:10792-10797(2015).
RN   [2]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=ATCC 10825 / DSM 20517 / JCM 9976 / NCIMB 9554 / NCTC 10469 / 32_A2;
RA   Varghese N.;
RL   Submitted (OCT-2016) to the EMBL/GenBank/DDBJ databases.
CC   -!- FUNCTION: Together with BzaB, catalyzes the conversion of
CC       aminoimidazole ribotide (AIR) to 5-hydroxybenzimidazole (5-HBI) in a
CC       radical S-adenosyl-L-methionine (SAM)-dependent reaction. Is thus
CC       involved in the anaerobic biosynthesis of dimethylbenzimidazole (DMB),
CC       the lower axial ligand of vitamin B12 (cobalamin). Requires BzaB for
CC       catalytic activity, as BzaA alone displays no activity.
CC       {ECO:0000269|PubMed:26246619}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=5-amino-1-(5-phospho-beta-D-ribosyl)imidazole + AH2 + S-
CC         adenosyl-L-methionine = 5'-deoxyadenosine + 5-hydroxybenzimidazole +
CC         A + formate + 2 H(+) + L-methionine + NH4(+) + phosphate;
CC         Xref=Rhea:RHEA:53504, ChEBI:CHEBI:13193, ChEBI:CHEBI:15378,
CC         ChEBI:CHEBI:15740, ChEBI:CHEBI:17319, ChEBI:CHEBI:17499,
CC         ChEBI:CHEBI:28938, ChEBI:CHEBI:43474, ChEBI:CHEBI:57844,
CC         ChEBI:CHEBI:59789, ChEBI:CHEBI:137404, ChEBI:CHEBI:137981;
CC         EC=4.1.99.23; Evidence={ECO:0000250|UniProtKB:P61425,
CC         ECO:0000305|PubMed:26246619};
CC   -!- COFACTOR:
CC       Name=[4Fe-4S] cluster; Xref=ChEBI:CHEBI:49883;
CC         Evidence={ECO:0000250|UniProtKB:P61425};
CC       Note=Binds 1 [4Fe-4S] cluster per subunit. The cluster is coordinated
CC       with 3 cysteines and an exchangeable S-adenosyl-L-methionine.
CC       {ECO:0000250|UniProtKB:Q9A6Q5};
CC   -!- PATHWAY: Cofactor biosynthesis; adenosylcobalamin biosynthesis.
CC       {ECO:0000305|PubMed:26246619}.
CC   -!- SIMILARITY: Belongs to the ThiC family. 5-hydroxybenzimidazole synthase
CC       subfamily. {ECO:0000305}.
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DR   EMBL; KT347435; AKV89410.1; -; Genomic_DNA.
DR   EMBL; FNJF01000014; SDP52039.1; -; Genomic_DNA.
DR   RefSeq; WP_074617801.1; NZ_FNJF01000014.1.
DR   AlphaFoldDB; A0A0K1TPY7; -.
DR   SMR; A0A0K1TPY7; -.
DR   STRING; 1736.ACH52_0364; -.
DR   EnsemblBacteria; SDP52039; SDP52039; SAMN04515624_11454.
DR   UniPathway; UPA00148; -.
DR   Proteomes; UP000182772; Unassembled WGS sequence.
DR   GO; GO:0051539; F:4 iron, 4 sulfur cluster binding; IEA:UniProtKB-KW.
DR   GO; GO:0016829; F:lyase activity; IEA:UniProtKB-KW.
DR   GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
DR   GO; GO:0009236; P:cobalamin biosynthetic process; IEA:UniProtKB-UniPathway.
DR   GO; GO:0009228; P:thiamine biosynthetic process; IEA:InterPro.
DR   Gene3D; 3.20.20.540; -; 1.
DR   InterPro; IPR038521; ThiC/Bza_core_dom.
DR   InterPro; IPR002817; ThiC/BzaA/B.
DR   PANTHER; PTHR30557; PTHR30557; 1.
DR   Pfam; PF01964; ThiC_Rad_SAM; 1.
DR   SFLD; SFLDF00407; phosphomethylpyrimidine_syntha; 1.
DR   TIGRFAMs; TIGR00190; thiC; 1.
PE   1: Evidence at protein level;
KW   4Fe-4S; Cobalamin biosynthesis; Iron; Iron-sulfur; Lyase; Metal-binding;
KW   S-adenosyl-L-methionine; Zinc.
FT   CHAIN           1..427
FT                   /note="5-hydroxybenzimidazole synthase BzaA"
FT                   /id="PRO_0000441745"
SQ   SEQUENCE   427 AA;  46636 MW;  C6EAC2870FC3EF05 CRC64;
     MTLLEKAKCG EITAEMQYVA EKEGVRPEFI CEGVANGDIV ILYSSRENIH PVAVGKGLLT
     KVSASVGMYE EADTVDGEMA KIDAAVKAHA DTIMDLSVRG PIEEMREKVL STVDRPVGTL
     PMYETLSVAE AKYGTALDMT PDDMFDMIEK QASQGVAFIA VHPGTTLSVI HRAKDEGRID
     PLVSYGGSHL IGWMLYNNTE NPLYTEFDRL IEICKKYDVV LSFADGMRPG CIADSLDHAQ
     VEELVILGGL VRRAREAGVQ VMVKGPGHVP LDEIATTVQL EKKLCYGAPY FVFGCLPTDA
     AAGYDHITSA IGGAVAAYAG ADFLCYVTPA EHIGMPNVDD VYQGVMASRI AAHAGDVAKG
     HPQAVKWDLD MSVARRAMNW KEQFKLSIDP ETAERVWRER STSFTSECTM CGKYCAMKIV
     EKYLRAE