ID A0A1G3QDA2_9SPIR Unreviewed; 392 AA.
AC A0A1G3QDA2;
DT 15-FEB-2017, integrated into UniProtKB/TrEMBL.
DT 15-FEB-2017, sequence version 1.
DT 27-MAR-2024, entry version 34.
DE RecName: Full=Riboflavin biosynthesis protein RibBA {ECO:0000256|HAMAP-Rule:MF_01283};
DE Includes:
DE RecName: Full=3,4-dihydroxy-2-butanone 4-phosphate synthase {ECO:0000256|HAMAP-Rule:MF_01283};
DE Short=DHBP synthase {ECO:0000256|HAMAP-Rule:MF_01283};
DE EC=4.1.99.12 {ECO:0000256|HAMAP-Rule:MF_01283};
DE Includes:
DE RecName: Full=GTP cyclohydrolase-2 {ECO:0000256|HAMAP-Rule:MF_01283};
DE EC=3.5.4.25 {ECO:0000256|HAMAP-Rule:MF_01283};
DE AltName: Full=GTP cyclohydrolase II {ECO:0000256|HAMAP-Rule:MF_01283};
GN Name=ribBA {ECO:0000256|HAMAP-Rule:MF_01283};
GN ORFNames=A2176_10210 {ECO:0000313|EMBL:OHD64672.1};
OS Spirochaetes bacterium RBG_13_51_14.
OC Bacteria; Spirochaetota.
OX NCBI_TaxID=1802193 {ECO:0000313|EMBL:OHD64672.1, ECO:0000313|Proteomes:UP000176595};
RN [1] {ECO:0000313|EMBL:OHD64672.1, ECO:0000313|Proteomes:UP000176595}
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RX PubMed=27774985; DOI=10.1038/ncomms13219;
RA Anantharaman K., Brown C.T., Hug L.A., Sharon I., Castelle C.J.,
RA Probst A.J., Thomas B.C., Singh A., Wilkins M.J., Karaoz U., Brodie E.L.,
RA Williams K.H., Hubbard S.S., Banfield J.F.;
RT "Thousands of microbial genomes shed light on interconnected biogeochemical
RT processes in an aquifer system.";
RL Nat. Commun. 7:13219-13219(2016).
CC -!- FUNCTION: Catalyzes the conversion of D-ribulose 5-phosphate to formate
CC and 3,4-dihydroxy-2-butanone 4-phosphate.
CC {ECO:0000256|ARBA:ARBA00002284, ECO:0000256|HAMAP-Rule:MF_01283}.
CC -!- FUNCTION: Catalyzes the conversion of GTP to 2,5-diamino-6-
CC ribosylamino-4(3H)-pyrimidinone 5'-phosphate (DARP), formate and
CC pyrophosphate. {ECO:0000256|HAMAP-Rule:MF_01283}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=D-ribulose 5-phosphate = (2S)-2-hydroxy-3-oxobutyl phosphate +
CC formate + H(+); Xref=Rhea:RHEA:18457, ChEBI:CHEBI:15378,
CC ChEBI:CHEBI:15740, ChEBI:CHEBI:58121, ChEBI:CHEBI:58830;
CC EC=4.1.99.12; Evidence={ECO:0000256|ARBA:ARBA00000141,
CC ECO:0000256|HAMAP-Rule:MF_01283};
CC -!- CATALYTIC ACTIVITY:
CC Reaction=GTP + 4 H2O = 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)-
CC pyrimidine + formate + 3 H(+) + 2 phosphate; Xref=Rhea:RHEA:23704,
CC ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:15740,
CC ChEBI:CHEBI:37565, ChEBI:CHEBI:43474, ChEBI:CHEBI:58614; EC=3.5.4.25;
CC Evidence={ECO:0000256|ARBA:ARBA00029293, ECO:0000256|HAMAP-
CC Rule:MF_01283};
CC -!- COFACTOR:
CC Name=Mg(2+); Xref=ChEBI:CHEBI:18420;
CC Evidence={ECO:0000256|HAMAP-Rule:MF_01283};
CC Name=Mn(2+); Xref=ChEBI:CHEBI:29035;
CC Evidence={ECO:0000256|HAMAP-Rule:MF_01283};
CC Note=Binds 2 divalent metal cations per subunit. Magnesium or
CC manganese. {ECO:0000256|HAMAP-Rule:MF_01283};
CC -!- COFACTOR:
CC Name=Mn(2+); Xref=ChEBI:CHEBI:29035;
CC Evidence={ECO:0000256|ARBA:ARBA00001936};
CC -!- COFACTOR:
CC Name=Zn(2+); Xref=ChEBI:CHEBI:29105;
CC Evidence={ECO:0000256|HAMAP-Rule:MF_01283};
CC Note=Binds 1 zinc ion per subunit. {ECO:0000256|HAMAP-Rule:MF_01283};
CC -!- PATHWAY: Cofactor biosynthesis; riboflavin biosynthesis; 2-hydroxy-3-
CC oxobutyl phosphate from D-ribulose 5-phosphate: step 1/1.
CC {ECO:0000256|ARBA:ARBA00004904, ECO:0000256|HAMAP-Rule:MF_01283}.
CC -!- PATHWAY: Cofactor biosynthesis; riboflavin biosynthesis; 5-amino-6-(D-
CC ribitylamino)uracil from GTP: step 1/4. {ECO:0000256|ARBA:ARBA00004853,
CC ECO:0000256|HAMAP-Rule:MF_01283}.
CC -!- SIMILARITY: In the C-terminal section; belongs to the GTP
CC cyclohydrolase II family. {ECO:0000256|HAMAP-Rule:MF_01283}.
CC -!- SIMILARITY: In the N-terminal section; belongs to the DHBP synthase
CC family. {ECO:0000256|ARBA:ARBA00005520, ECO:0000256|HAMAP-
CC Rule:MF_01283}.
CC -!- CAUTION: The sequence shown here is derived from an EMBL/GenBank/DDBJ
CC whole genome shotgun (WGS) entry which is preliminary data.
CC {ECO:0000313|EMBL:OHD64672.1}.
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DR EMBL; MIBH01000042; OHD64672.1; -; Genomic_DNA.
DR AlphaFoldDB; A0A1G3QDA2; -.
DR STRING; 1802193.A2176_10210; -.
DR UniPathway; UPA00275; UER00399.
DR Proteomes; UP000176595; Unassembled WGS sequence.
DR GO; GO:0008686; F:3,4-dihydroxy-2-butanone-4-phosphate synthase activity; IEA:UniProtKB-UniRule.
DR GO; GO:0005525; F:GTP binding; IEA:UniProtKB-KW.
DR GO; GO:0003935; F:GTP cyclohydrolase II activity; IEA:UniProtKB-UniRule.
DR GO; GO:0000287; F:magnesium ion binding; IEA:UniProtKB-UniRule.
DR GO; GO:0030145; F:manganese ion binding; IEA:UniProtKB-UniRule.
DR GO; GO:0008270; F:zinc ion binding; IEA:UniProtKB-UniRule.
DR GO; GO:0009231; P:riboflavin biosynthetic process; IEA:UniProtKB-UniRule.
DR CDD; cd00641; GTP_cyclohydro2; 1.
DR Gene3D; 3.90.870.10; DHBP synthase; 1.
DR Gene3D; 3.40.50.10990; GTP cyclohydrolase II; 1.
DR HAMAP; MF_00179; RibA; 1.
DR HAMAP; MF_01283; RibBA; 1.
DR InterPro; IPR017945; DHBP_synth_RibB-like_a/b_dom.
DR InterPro; IPR000422; DHBP_synthase_RibB.
DR InterPro; IPR032677; GTP_cyclohydro_II.
DR InterPro; IPR000926; RibA.
DR InterPro; IPR036144; RibA-like_sf.
DR InterPro; IPR016299; Riboflavin_synth_RibBA.
DR NCBIfam; TIGR00505; ribA; 1.
DR NCBIfam; TIGR00506; ribB; 1.
DR PANTHER; PTHR21327; GTP CYCLOHYDROLASE II-RELATED; 1.
DR PANTHER; PTHR21327:SF48; RIBOFLAVIN BIOSYNTHESIS PROTEIN RIBBA; 1.
DR Pfam; PF00926; DHBP_synthase; 1.
DR Pfam; PF00925; GTP_cyclohydro2; 1.
DR PIRSF; PIRSF001259; RibA; 1.
DR SUPFAM; SSF142695; RibA-like; 1.
DR SUPFAM; SSF55821; YrdC/RibB; 1.
PE 3: Inferred from homology;
KW GTP-binding {ECO:0000256|ARBA:ARBA00023134, ECO:0000256|HAMAP-
KW Rule:MF_01283};
KW Hydrolase {ECO:0000256|ARBA:ARBA00022801, ECO:0000256|HAMAP-Rule:MF_01283};
KW Lyase {ECO:0000256|ARBA:ARBA00023239, ECO:0000256|HAMAP-Rule:MF_01283};
KW Magnesium {ECO:0000256|ARBA:ARBA00022842, ECO:0000256|HAMAP-Rule:MF_01283};
KW Manganese {ECO:0000256|ARBA:ARBA00023211, ECO:0000256|HAMAP-Rule:MF_01283};
KW Metal-binding {ECO:0000256|ARBA:ARBA00022723, ECO:0000256|HAMAP-
KW Rule:MF_01283};
KW Multifunctional enzyme {ECO:0000256|ARBA:ARBA00023268, ECO:0000256|HAMAP-
KW Rule:MF_01283};
KW Nucleotide-binding {ECO:0000256|ARBA:ARBA00022741, ECO:0000256|HAMAP-
KW Rule:MF_01283};
KW Riboflavin biosynthesis {ECO:0000256|ARBA:ARBA00022619, ECO:0000256|HAMAP-
KW Rule:MF_01283}; Zinc {ECO:0000256|HAMAP-Rule:MF_01283}.
FT DOMAIN 191..356
FT /note="GTP cyclohydrolase II"
FT /evidence="ECO:0000259|Pfam:PF00925"
FT REGION 1..184
FT /note="DHBP synthase"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT REGION 185..392
FT /note="GTP cyclohydrolase II"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT ACT_SITE 312
FT /note="Proton acceptor; for GTP cyclohydrolase activity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT ACT_SITE 314
FT /note="Nucleophile; for GTP cyclohydrolase activity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 10..11
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 11
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="2"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 11
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="1"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 15
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 123..127
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 126
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="2"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 147
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 235..239
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 240
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 251
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 253
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 256
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 278..280
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 300
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 335
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 340
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT SITE 109
FT /note="Essential for DHBP synthase activity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT SITE 147
FT /note="Essential for DHBP synthase activity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
SQ SEQUENCE 392 AA; 43224 MW; B22DDC57316E7942 CRC64;
MIILVDNEDR ENEGDLVVAA EFCTSSVINF MATYGRGLIC VPMQQVRARE LELDLMVENN
QDKYGTAFTV SVDAREGTTT GISAHDRART VQVLIHDDTK PGDLRKPGHI FPLAARNGGV
LVRAGHTEGV VDLTRLAGLK PAGVICEILN EDGTMARRPD LDRFAVKHNL KIATIADLIK
FRQHKERLVH RVSEANLPTA YGGFTIIAYQ TEVGEATHVA LVKGNIEGKE NVLVRVHSEC
LTGDVFASLR CDCGSQIHKA MEMVDREGQG VILYMRQEGR GIGLGNKIKA YHLQDKGMDT
VEANIELGFP ADLRDYGIGA QILVDLGLHK IRLLTNNPKK VIGLDGYGLE IVERVPIEVE
PHSANVRYLR AKRDKMGHLI LGGEELIKKN NE
//
