ID A0A1H6UIT2_9BACT Unreviewed; 417 AA.
AC A0A1H6UIT2;
DT 22-NOV-2017, integrated into UniProtKB/TrEMBL.
DT 22-NOV-2017, sequence version 1.
DT 27-MAR-2024, entry version 27.
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=SAMN05216327_104371 {ECO:0000313|EMBL:SEI88075.1};
OS Dyadobacter sp. SG02.
OC Bacteria; Bacteroidota; Cytophagia; Cytophagales; Spirosomataceae;
OC Dyadobacter.
OX NCBI_TaxID=1855291 {ECO:0000313|EMBL:SEI88075.1, ECO:0000313|Proteomes:UP000199631};
RN [1] {ECO:0000313|EMBL:SEI88075.1, ECO:0000313|Proteomes:UP000199631}
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=SG02 {ECO:0000313|EMBL:SEI88075.1,
RC ECO:0000313|Proteomes:UP000199631};
RA de Groot N.N.;
RL Submitted (OCT-2016) to the EMBL/GenBank/DDBJ databases.
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}.
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DR EMBL; FNYL01000004; SEI88075.1; -; Genomic_DNA.
DR AlphaFoldDB; A0A1H6UIT2; -.
DR STRING; 1855291.SAMN05216327_104371; -.
DR OrthoDB; 9793111at2; -.
DR UniPathway; UPA00275; UER00399.
DR Proteomes; UP000199631; 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_00180; RibB; 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 219..380
FT /note="GTP cyclohydrolase II"
FT /evidence="ECO:0000259|Pfam:PF00925"
FT REGION 1..209
FT /note="DHBP synthase"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT REGION 210..417
FT /note="GTP cyclohydrolase II"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT ACT_SITE 337
FT /note="Proton acceptor; for GTP cyclohydrolase activity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT ACT_SITE 339
FT /note="Nucleophile; for GTP cyclohydrolase activity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 34..35
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 35
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="1"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 35
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="2"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 39
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 148..152
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 151
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="2"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 172
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 260..264
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 265
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 276
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 278
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 281
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 303..305
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 325
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 360
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 365
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT SITE 134
FT /note="Essential for DHBP synthase activity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT SITE 172
FT /note="Essential for DHBP synthase activity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
SQ SEQUENCE 417 AA; 45913 MW; 5C6BFAB9C81790C2 CRC64;
MSNNSNPIAL DSIEDAIEAI KRGELIIVVD DEDRENEGDF ICAAELVTPE IVNFMAREGR
GLICVPITEE RCAELELEMM VGNNTALHET AFTVSVDLLG HGCTTGISAS DRSKTIQALV
SKDTKPSDLG RPGHIFPLKA KRGGVLRRTG HTEAAIDFPR LAGLSPAGVL VEILNEDGSM
ARLPQLREIA NRFNLKLVSI KDLIEYRLRE ESLIKREIGV DMPTKFGHFD LIAYRQINTG
DLHLALVKGT WEKDEPVLVR VHSSCVTGDI FGSCRCDCGP QLHAAMEMVD QAGKGVIVYM
NQEGRGIGLL NKLRAYKLQE MGRDTVEANL ELGFPMDDRD YGVGAQILRD LELTKIKLIT
NNPKKRAGLI GYGLEIVDSV GIEIPSNPYN EKYLLTKRDK MGHSLSNLTI VGHNKGL
//
