RIBA_HELPS
ID RIBA_HELPS Reviewed; 192 AA.
AC B2UT29;
DT 24-MAR-2009, integrated into UniProtKB/Swiss-Prot.
DT 01-JUL-2008, sequence version 1.
DT 03-AUG-2022, entry version 69.
DE RecName: Full=GTP cyclohydrolase-2 {ECO:0000255|HAMAP-Rule:MF_00179};
DE EC=3.5.4.25 {ECO:0000255|HAMAP-Rule:MF_00179};
DE AltName: Full=GTP cyclohydrolase II {ECO:0000255|HAMAP-Rule:MF_00179};
GN Name=ribA {ECO:0000255|HAMAP-Rule:MF_00179}; OrderedLocusNames=HPSH_02805;
OS Helicobacter pylori (strain Shi470).
OC Bacteria; Proteobacteria; Epsilonproteobacteria; Campylobacterales;
OC Helicobacteraceae; Helicobacter.
OX NCBI_TaxID=512562;
RN [1]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=Shi470;
RA Kersulyte D., Kalia A., Gilman R.H., Berg D.E.;
RT "Genome sequence of Helicobacter pylori from the remote Amazon: traces of
RT Asian ancestry of the first Americans.";
RL Submitted (MAY-2008) to the EMBL/GenBank/DDBJ databases.
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:0000255|HAMAP-Rule:MF_00179}.
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:0000255|HAMAP-Rule:MF_00179};
CC -!- COFACTOR:
CC Name=Zn(2+); Xref=ChEBI:CHEBI:29105;
CC Evidence={ECO:0000255|HAMAP-Rule:MF_00179};
CC Note=Binds 1 zinc ion per subunit. {ECO:0000255|HAMAP-Rule:MF_00179};
CC -!- PATHWAY: Cofactor biosynthesis; riboflavin biosynthesis; 5-amino-6-(D-
CC ribitylamino)uracil from GTP: step 1/4. {ECO:0000255|HAMAP-
CC Rule:MF_00179}.
CC -!- SIMILARITY: Belongs to the GTP cyclohydrolase II family.
CC {ECO:0000255|HAMAP-Rule:MF_00179}.
CC ---------------------------------------------------------------------------
CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC ---------------------------------------------------------------------------
DR EMBL; CP001072; ACD48011.1; -; Genomic_DNA.
DR RefSeq; WP_000825049.1; NC_010698.2.
DR AlphaFoldDB; B2UT29; -.
DR SMR; B2UT29; -.
DR KEGG; hps:HPSH_02805; -.
DR HOGENOM; CLU_020273_2_1_7; -.
DR OMA; GQGFILY; -.
DR UniPathway; UPA00275; UER00400.
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: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; 3.40.50.10990; -; 1.
DR HAMAP; MF_00179; RibA; 1.
DR InterPro; IPR032677; GTP_cyclohydro_II.
DR InterPro; IPR000926; RibA.
DR InterPro; IPR036144; RibA-like_sf.
DR Pfam; PF00925; GTP_cyclohydro2; 1.
DR SUPFAM; SSF142695; SSF142695; 1.
DR TIGRFAMs; TIGR00505; ribA; 1.
PE 3: Inferred from homology;
KW GTP-binding; Hydrolase; Metal-binding; Nucleotide-binding;
KW Riboflavin biosynthesis; Zinc.
FT CHAIN 1..192
FT /note="GTP cyclohydrolase-2"
FT /id="PRO_1000098268"
FT ACT_SITE 126
FT /note="Proton acceptor"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00179"
FT ACT_SITE 128
FT /note="Nucleophile"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00179"
FT BINDING 50..54
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00179"
FT BINDING 55
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00179"
FT BINDING 66
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00179"
FT BINDING 68
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00179"
FT BINDING 92..94
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00179"
FT BINDING 114
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00179"
FT BINDING 149
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00179"
FT BINDING 154
FT /ligand="GTP"
FT /ligand_id="ChEBI:CHEBI:37565"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00179"
SQ SEQUENCE 192 AA; 21566 MW; 86D6DB9D8118258E CRC64;
MKRLEVSNQA KLPTQFGEFC IQCFREKGSN GSKEHLVVFT PNFSQNPLVR LHSECLTGDA
LGSQKCDCGG ALQIALERIS KEGGLVIYLR QEGRGIGLFN KVNAYALQDK GYDTIQANEM
IGFKDDERDY SIAGEILEYY GIKKMRLLTN NPKKIAALEK YAEVTRESLI VCANEHNQGY
LEVKKLKMGH LL
