ID H6L2E0_SAPGL Unreviewed; 415 AA.
AC H6L2E0;
DT 18-APR-2012, integrated into UniProtKB/TrEMBL.
DT 18-APR-2012, sequence version 1.
DT 27-MAR-2024, entry version 84.
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 OrderedLocusNames=SGRA_0862 {ECO:0000313|EMBL:AFC23598.1};
OS Saprospira grandis (strain Lewin).
OC Bacteria; Bacteroidota; Saprospiria; Saprospirales; Saprospiraceae;
OC Saprospira.
OX NCBI_TaxID=984262 {ECO:0000313|EMBL:AFC23598.1, ECO:0000313|Proteomes:UP000007519};
RN [1] {ECO:0000313|EMBL:AFC23598.1, ECO:0000313|Proteomes:UP000007519}
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=Lewin {ECO:0000313|EMBL:AFC23598.1,
RC ECO:0000313|Proteomes:UP000007519};
RX PubMed=22675601; DOI=10.4056/sigs.2445005;
RA Saw J.H., Yuryev A., Kanbe M., Hou S., Young A.G., Aizawa S., Alam M.;
RT "Complete genome sequencing and analysis of Saprospira grandis str. Lewin,
RT a predatory marine bacterium.";
RL Stand. Genomic Sci. 6:84-93(2012).
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; CP002831; AFC23598.1; -; Genomic_DNA.
DR RefSeq; WP_015691249.1; NC_016940.1.
DR AlphaFoldDB; H6L2E0; -.
DR STRING; 984262.SGRA_0862; -.
DR KEGG; sgn:SGRA_0862; -.
DR eggNOG; COG0108; Bacteria.
DR eggNOG; COG0807; Bacteria.
DR HOGENOM; CLU_020273_1_2_10; -.
DR OrthoDB; 9793111at2; -.
DR UniPathway; UPA00275; UER00399.
DR Proteomes; UP000007519; Chromosome.
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}; Reference proteome {ECO:0000313|Proteomes:UP000007519};
KW Riboflavin biosynthesis {ECO:0000256|ARBA:ARBA00022619, ECO:0000256|HAMAP-
KW Rule:MF_01283}; Zinc {ECO:0000256|HAMAP-Rule:MF_01283}.
FT DOMAIN 220..384
FT /note="GTP cyclohydrolase II"
FT /evidence="ECO:0000259|Pfam:PF00925"
FT REGION 1..213
FT /note="DHBP synthase"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT REGION 214..415
FT /note="GTP cyclohydrolase II"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT ACT_SITE 341
FT /note="Proton acceptor; for GTP cyclohydrolase activity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT ACT_SITE 343
FT /note="Nucleophile; for GTP cyclohydrolase activity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 38..39
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 39
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="1"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 39
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="2"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 43
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 152..156
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 155
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="2"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 176
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 264..268
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 269
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 280
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 282
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 285
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 307..309
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 329
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 364
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 369
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT SITE 138
FT /note="Essential for DHBP synthase activity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT SITE 176
FT /note="Essential for DHBP synthase activity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
SQ SEQUENCE 415 AA; 46370 MW; 64762DA50097329E CRC64;
MSGNQQNESL DRKLDSIEAA IQDIRDGKII IVVDDEDREN EGDFICAAEK ITPELVNFMA
THGRGLICTP LTEDRCRELN LKPMVQTNTS HHETAFTISV DLIGHGCSTG ISAYDRSTGI
RLLTDPNTSW TDYARPGHIF PLIAKDGGVL RRAGHTEAAV DLARLAGLAP AGVLVEILNE
DGTMARLPDL VKVAERFDLK IISIADLIKY RVENEKLVER LIDVQMPTEY GDFQLIAFED
KTRNETHLAL KKGDWKADEP VLVRVHSSCQ TGDILGSLRC DCGPQLHAAM KQIEAEGKGL
LLYIMQEGRG IGLLNKLKAY KLQEQGYDTV EANLMLGFKA DERDYGIGAQ ILRELKISKM
RLMTNNPTKR IGLIGYGLEI VENVELEIEP NEHNEFYLFT KRDKMGHTIL DKKKS
//
