RIBBA_SYNY3
ID RIBBA_SYNY3 Reviewed; 556 AA.
AC P74104;
DT 01-DEC-2000, integrated into UniProtKB/Swiss-Prot.
DT 01-FEB-1997, sequence version 1.
DT 03-AUG-2022, entry version 136.
DE RecName: Full=Riboflavin biosynthesis protein RibBA;
DE Includes:
DE RecName: Full=3,4-dihydroxy-2-butanone 4-phosphate synthase;
DE Short=DHBP synthase;
DE EC=4.1.99.12;
DE Includes:
DE RecName: Full=GTP cyclohydrolase-2;
DE EC=3.5.4.25;
DE AltName: Full=GTP cyclohydrolase II;
GN Name=ribBA; Synonyms=ribA; OrderedLocusNames=sll1894;
OS Synechocystis sp. (strain PCC 6803 / Kazusa).
OC Bacteria; Cyanobacteria; Synechococcales; Merismopediaceae; Synechocystis;
OC unclassified Synechocystis.
OX NCBI_TaxID=1111708;
RN [1]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=PCC 6803 / Kazusa;
RX PubMed=8905231; DOI=10.1093/dnares/3.3.109;
RA Kaneko T., Sato S., Kotani H., Tanaka A., Asamizu E., Nakamura Y.,
RA Miyajima N., Hirosawa M., Sugiura M., Sasamoto S., Kimura T., Hosouchi T.,
RA Matsuno A., Muraki A., Nakazaki N., Naruo K., Okumura S., Shimpo S.,
RA Takeuchi C., Wada T., Watanabe A., Yamada M., Yasuda M., Tabata S.;
RT "Sequence analysis of the genome of the unicellular cyanobacterium
RT Synechocystis sp. strain PCC6803. II. Sequence determination of the entire
RT genome and assignment of potential protein-coding regions.";
RL DNA Res. 3:109-136(1996).
CC -!- FUNCTION: Catalyzes the conversion of D-ribulose 5-phosphate to formate
CC and 3,4-dihydroxy-2-butanone 4-phosphate. {ECO:0000250}.
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:0000250}.
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;
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 -!- COFACTOR:
CC Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000250};
CC Name=Mn(2+); Xref=ChEBI:CHEBI:29035; Evidence={ECO:0000250};
CC Note=Binds 2 divalent metal cations per subunit. Magnesium or
CC manganese. {ECO:0000250};
CC -!- COFACTOR:
CC Name=Zn(2+); Xref=ChEBI:CHEBI:29105; Evidence={ECO:0000250};
CC Note=Binds 1 zinc ion per subunit. {ECO:0000250};
CC -!- PATHWAY: Cofactor biosynthesis; riboflavin biosynthesis; 2-hydroxy-3-
CC oxobutyl phosphate from D-ribulose 5-phosphate: step 1/1.
CC -!- PATHWAY: Cofactor biosynthesis; riboflavin biosynthesis; 5-amino-6-(D-
CC ribitylamino)uracil from GTP: step 1/4.
CC -!- SIMILARITY: In the N-terminal section; belongs to the DHBP synthase
CC family. {ECO:0000305}.
CC -!- SIMILARITY: In the central section; belongs to the GTP cyclohydrolase
CC II family. {ECO:0000305}.
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DR EMBL; BA000022; BAA18190.1; -; Genomic_DNA.
DR PIR; S75629; S75629.
DR AlphaFoldDB; P74104; -.
DR SMR; P74104; -.
DR STRING; 1148.1653275; -.
DR PaxDb; P74104; -.
DR EnsemblBacteria; BAA18190; BAA18190; BAA18190.
DR KEGG; syn:sll1894; -.
DR eggNOG; COG0108; Bacteria.
DR eggNOG; COG0807; Bacteria.
DR InParanoid; P74104; -.
DR OMA; ECRGLIC; -.
DR PhylomeDB; P74104; -.
DR UniPathway; UPA00275; UER00399.
DR UniPathway; UPA00275; UER00400.
DR Proteomes; UP000001425; Chromosome.
DR GO; GO:0005829; C:cytosol; IBA:GO_Central.
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; IBA:GO_Central.
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; IBA:GO_Central.
DR CDD; cd00641; GTP_cyclohydro2; 1.
DR Gene3D; 3.40.50.10990; -; 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 Pfam; PF00926; DHBP_synthase; 1.
DR Pfam; PF00925; GTP_cyclohydro2; 1.
DR SUPFAM; SSF142695; SSF142695; 1.
DR SUPFAM; SSF55821; SSF55821; 1.
DR TIGRFAMs; TIGR00505; ribA; 1.
DR TIGRFAMs; TIGR00506; ribB; 1.
PE 3: Inferred from homology;
KW GTP-binding; Hydrolase; Lyase; Magnesium; Manganese; Metal-binding;
KW Multifunctional enzyme; Nucleotide-binding; Reference proteome;
KW Riboflavin biosynthesis; Zinc.
FT CHAIN 1..556
FT /note="Riboflavin biosynthesis protein RibBA"
FT /id="PRO_0000151743"
FT REGION 1..202
FT /note="DHBP synthase"
FT REGION 203..402
FT /note="GTP cyclohydrolase II"
FT REGION 403..556
FT /note="Unknown"
FT ACT_SITE 332
FT /note="Proton acceptor; for GTP cyclohydrolase activity"
FT /evidence="ECO:0000255"
FT ACT_SITE 334
FT /note="Nucleophile; for GTP cyclohydrolase activity"
FT /evidence="ECO:0000250"
FT BINDING 26..27
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000250"
FT BINDING 27
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="1"
FT /evidence="ECO:0000250"
FT BINDING 27
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="2"
FT /evidence="ECO:0000250"
FT BINDING 31
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000250"
FT BINDING 141..145
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000250"
FT BINDING 144
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="2"
FT /evidence="ECO:0000250"
FT BINDING 165
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000250"
FT BINDING 255..259
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000250"
FT BINDING 260
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000250"
FT BINDING 271
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000250"
FT BINDING 273
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000250"
FT BINDING 276
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000250"
FT BINDING 298..300
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000250"
FT BINDING 320
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000250"
FT BINDING 355
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000250"
FT BINDING 360
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000250"
FT SITE 127
FT /note="Essential for DHBP synthase activity"
FT /evidence="ECO:0000250"
FT SITE 165
FT /note="Essential for DHBP synthase activity"
FT /evidence="ECO:0000250"
SQ SEQUENCE 556 AA; 61682 MW; 57E37AD966D2B04F CRC64;
MFDAIDAALA DIKAGKAVVV VDDENRENEG DLICAAQFAT PALVNFMAVE ARGLICLAMT
GDRLDELDLP LMVSKNTDSN QTAFTVSIDA APHLGVTTGI SAEDRARTIQ IAINPVTRPE
DLSRPGHIFP LRAKTGGVLK RAGHTEAAVD LSRLAGLYPA GVICEIQNAD GSMARLPELV
EYARKYDLKL ISIADLISYR LQHDRFVQRE TICEFPSQFG EFKLYAYRNL LDQTEHIAIV
KGDPSEFGQQ PVMVRMHSEC LTGDALGSLR CDCRMQLQAA LKMLENHGLG VVVYLRQEGR
GIGLVNKLKA YSLQDLGYDT VEANERLGFP ADLRDYGMGA QMLNDLGVKQ IRLITNNPRK
IAGLKGYGLE IVERVPLLIE ANDYNSHYLT TKAEKLGHWL VKNYLLAIAI KFTPNVASAQ
QRYEKLEKIR ALLQGTPLMV HEDNRPVAIA LFGKNSLIFH VGLDQNLPSG QPWQKHDHSP
YPALVKDFLV QLKQWPDLQA LAFLIAQGKD PMETLQVSLD RENVSFADLT ADALNQWQPQ
TVYTYSKQGS GEMTNR
