ID K9X7L3_9NOST Unreviewed; 557 AA.
AC K9X7L3;
DT 06-MAR-2013, integrated into UniProtKB/TrEMBL.
DT 06-MAR-2013, sequence version 1.
DT 27-MAR-2024, entry version 70.
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=Cylst_5642 {ECO:0000313|EMBL:AFZ27642.1};
OS Cylindrospermum stagnale PCC 7417.
OC Bacteria; Cyanobacteriota; Cyanophyceae; Nostocales; Nostocaceae;
OC Cylindrospermum.
OX NCBI_TaxID=56107 {ECO:0000313|EMBL:AFZ27642.1, ECO:0000313|Proteomes:UP000010475};
RN [1] {ECO:0000313|EMBL:AFZ27642.1, ECO:0000313|Proteomes:UP000010475}
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=PCC 7417 {ECO:0000313|EMBL:AFZ27642.1,
RC ECO:0000313|Proteomes:UP000010475};
RG US DOE Joint Genome Institute;
RA Gugger M., Coursin T., Rippka R., Tandeau De Marsac N., Huntemann M.,
RA Wei C.-L., Han J., Detter J.C., Han C., Tapia R., Chen A., Kyrpides N.,
RA Mavromatis K., Markowitz V., Szeto E., Ivanova N., Pagani I., Pati A.,
RA Goodwin L., Nordberg H.P., Cantor M.N., Hua S.X., Woyke T., Kerfeld C.A.;
RT "Finished chromosome of genome of Cylindrospermum stagnale PCC 7417.";
RL Submitted (JUN-2012) 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; CP003642; AFZ27642.1; -; Genomic_DNA.
DR RefSeq; WP_015210876.1; NC_019757.1.
DR AlphaFoldDB; K9X7L3; -.
DR STRING; 56107.Cylst_5642; -.
DR KEGG; csg:Cylst_5642; -.
DR PATRIC; fig|56107.3.peg.6207; -.
DR eggNOG; COG0108; Bacteria.
DR eggNOG; COG0807; Bacteria.
DR HOGENOM; CLU_020273_0_0_3; -.
DR OrthoDB; 9793111at2; -.
DR UniPathway; UPA00275; UER00399.
DR Proteomes; UP000010475; 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 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:UP000010475};
KW Riboflavin biosynthesis {ECO:0000256|ARBA:ARBA00022619, ECO:0000256|HAMAP-
KW Rule:MF_01283}; Zinc {ECO:0000256|HAMAP-Rule:MF_01283}.
FT DOMAIN 222..386
FT /note="GTP cyclohydrolase II"
FT /evidence="ECO:0000259|Pfam:PF00925"
FT REGION 1..212
FT /note="DHBP synthase"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT REGION 213..557
FT /note="GTP cyclohydrolase II"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT ACT_SITE 342
FT /note="Proton acceptor; for GTP cyclohydrolase activity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT ACT_SITE 344
FT /note="Nucleophile; for GTP cyclohydrolase activity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 36..37
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 37
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="1"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 37
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="2"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 41
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 151..155
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 154
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="2"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 175
FT /ligand="D-ribulose 5-phosphate"
FT /ligand_id="ChEBI:CHEBI:58121"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 265..269
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 270
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="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 283
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 286
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 308..310
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT BINDING 330
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 BINDING 370
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT SITE 137
FT /note="Essential for DHBP synthase activity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
FT SITE 175
FT /note="Essential for DHBP synthase activity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01283"
SQ SEQUENCE 557 AA; 61981 MW; A76763F2067260BB CRC64;
MSEPKTTLTF KFDSIDAALA DLKAGRVIVV VDDENRENEG DLICAAQFAT PDMINFMAVE
ARGLICLAMT GDRLDELNLP LMVSNITDTN QTAFTVSIDA GPQLGVTTGI SAEDRARTIQ
VALNPATKPE DLRRPGHIFP IRAKQGGVLK RAGHTEAAVD LSRLAGLYPA GVICEIQNSD
GSMARLNQLI EYAKTHKLKI ISIADLISYR LQHDRLVIRE TITELPTQFG HFRIYGYRHT
LDNHEHVAVV KGDPATFQDE AVMVRMHSEC LTGDALGSLR CDCRMQLQAA LKMIESAGQG
VVVYLRQEGR GIGLINKLKA YSLQDMGLDT VEANERLGFP ADLRDYGMGA QMLMDLGIKK
IRLITNNPRK IAGVKGYGLE VVDRVPLLIE ATDYNSYYLA TKAQKLGHML LQTYLVTVAI
HWLDDPQLVT LRYERLEKLR HLAKINDLLL QEEARPLAIA LFDKPSLTVH LGFDQAKVAD
ADWFEQTGHP YLQAIFQILD DLVTLPYVQK VEFLISPGSD PLSNLQVQLD REIFAPKTVP
SSICDRLETQ QIYSFSQ
//