Skip Header

You are using a version of browser that may not display all the features of this website. Please consider upgrading your browser.
Protein

GTP cyclohydrolase-2

Gene

ribA

Organism
Escherichia coli (strain K12)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

Catalyzes the conversion of GTP to 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate (DARP), formate and pyrophosphate.1 Publication

Catalytic activityi

GTP + 3 H2O = formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate.

Cofactori

Zn2+2 PublicationsNote: Binds 1 zinc ion per subunit.2 Publications

Enzyme regulationi

Competitively inhibited by pyrophosphate.2 Publications

Kineticsi

  1. KM=41 µM for GTP1 Publication

    pH dependencei

    Optimum pH is 8.5.1 Publication

    Pathwayi: riboflavin biosynthesis

    This protein is involved in step 1 of the subpathway that synthesizes 5-amino-6-(D-ribitylamino)uracil from GTP.
    Proteins known to be involved in the 4 steps of the subpathway in this organism are:
    1. GTP cyclohydrolase-2 (ribA)
    2. Riboflavin biosynthesis protein RibD (ribD)
    3. Riboflavin biosynthesis protein RibD (ribD)
    4. 5-amino-6-(5-phospho-D-ribitylamino)uracil phosphatase YbjI (ybjI), 5-amino-6-(5-phospho-D-ribitylamino)uracil phosphatase YigB (yigB)
    This subpathway is part of the pathway riboflavin biosynthesis, which is itself part of Cofactor biosynthesis.
    View all proteins of this organism that are known to be involved in the subpathway that synthesizes 5-amino-6-(D-ribitylamino)uracil from GTP, the pathway riboflavin biosynthesis and in Cofactor biosynthesis.

    Sites

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Metal bindingi54 – 541Zinc; catalytic
    Metal bindingi65 – 651Zinc; catalytic
    Metal bindingi67 – 671Zinc; catalytic
    Binding sitei70 – 701GTP
    Binding sitei114 – 1141GTP
    Active sitei126 – 1261Proton acceptorSequence analysis
    Active sitei128 – 1281Nucleophile
    Binding sitei149 – 1491GTP
    Binding sitei154 – 1541GTP

    Regions

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Nucleotide bindingi49 – 535GTP
    Nucleotide bindingi92 – 943GTP

    GO - Molecular functioni

    • GTP binding Source: UniProtKB-KW
    • GTP cyclohydrolase II activity Source: EcoCyc
    • zinc ion binding Source: UniProtKB-HAMAP

    GO - Biological processi

    Complete GO annotation...

    Keywords - Molecular functioni

    Hydrolase

    Keywords - Biological processi

    Riboflavin biosynthesis

    Keywords - Ligandi

    GTP-binding, Metal-binding, Nucleotide-binding, Zinc

    Enzyme and pathway databases

    BioCyciEcoCyc:GTP-CYCLOHYDRO-II-MONOMER.
    ECOL316407:JW1269-MONOMER.
    MetaCyc:GTP-CYCLOHYDRO-II-MONOMER.
    UniPathwayiUPA00275; UER00400.

    Names & Taxonomyi

    Protein namesi
    Recommended name:
    GTP cyclohydrolase-2 (EC:3.5.4.25)
    Alternative name(s):
    GTP cyclohydrolase II
    Gene namesi
    Name:ribA
    Ordered Locus Names:b1277, JW1269
    OrganismiEscherichia coli (strain K12)
    Taxonomic identifieri83333 [NCBI]
    Taxonomic lineageiBacteriaProteobacteriaGammaproteobacteriaEnterobacterialesEnterobacteriaceaeEscherichia
    Proteomesi
    • UP000000318 Componenti: Chromosome
    • UP000000625 Componenti: Chromosome

    Organism-specific databases

    EcoGeneiEG11331. ribA.

    Pathology & Biotechi

    Mutagenesis

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Mutagenesisi54 – 541C → S: Loss of zinc binding. Loss of ring-opening activity. Can still remove phosphate from GTP. 1 Publication
    Mutagenesisi65 – 651C → S: Loss of zinc binding. Loss of ring-opening activity. Can still remove phosphate from GTP. 1 Publication
    Mutagenesisi67 – 671C → S: Loss of zinc binding. Loss of ring-opening activity. Can still remove phosphate from GTP. 1 Publication

    PTM / Processingi

    Molecule processing

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Chaini1 – 196196GTP cyclohydrolase-2PRO_0000151754Add
    BLAST

    Proteomic databases

    EPDiP0A7I7.
    PaxDbiP0A7I7.
    PRIDEiP0A7I7.

    Interactioni

    Subunit structurei

    Homodimer.2 Publications

    Binary interactionsi

    WithEntry#Exp.IntActNotes
    pyrFP082442EBI-1123314,EBI-1123202

    Protein-protein interaction databases

    DIPiDIP-36049N.
    IntActiP0A7I7. 2 interactions.
    STRINGi511145.b1277.

    Structurei

    Secondary structure

    1
    196
    Legend: HelixTurnBeta strand
    Show more details
    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Beta strandi3 – 1311Combined sources
    Beta strandi16 – 2510Combined sources
    Turni26 – 283Combined sources
    Beta strandi31 – 388Combined sources
    Beta strandi42 – 443Combined sources
    Beta strandi46 – 527Combined sources
    Helixi55 – 584Combined sources
    Beta strandi63 – 664Combined sources
    Helixi67 – 8115Combined sources
    Beta strandi83 – 897Combined sources
    Helixi92 – 954Combined sources
    Helixi98 – 10912Combined sources
    Helixi114 – 1207Combined sources
    Helixi131 – 1399Combined sources
    Beta strandi144 – 1485Combined sources
    Helixi152 – 1609Combined sources
    Beta strandi165 – 1695Combined sources

    3D structure databases

    Select the link destinations:
    PDBei
    RCSB PDBi
    PDBji
    Links Updated
    EntryMethodResolution (Å)ChainPositionsPDBsum
    2BZ0X-ray2.60A/B1-196[»]
    2BZ1X-ray1.54A1-196[»]
    ProteinModelPortaliP0A7I7.
    SMRiP0A7I7. Positions 1-173.
    ModBaseiSearch...
    MobiDBiSearch...

    Miscellaneous databases

    EvolutionaryTraceiP0A7I7.

    Family & Domainsi

    Sequence similaritiesi

    Belongs to the GTP cyclohydrolase II family.Curated

    Phylogenomic databases

    eggNOGiENOG4107T1C. Bacteria.
    COG0807. LUCA.
    HOGENOMiHOG000115442.
    InParanoidiP0A7I7.
    KOiK01497.
    OMAiPTPFGVF.
    PhylomeDBiP0A7I7.

    Family and domain databases

    CDDicd00641. GTP_cyclohydro2. 1 hit.
    HAMAPiMF_00179. RibA. 1 hit.
    InterProiIPR032677. GTP_cyclohydro_II.
    IPR000926. RibA.
    [Graphical view]
    PfamiPF00925. GTP_cyclohydro2. 1 hit.
    [Graphical view]
    SUPFAMiSSF142695. SSF142695. 1 hit.
    TIGRFAMsiTIGR00505. ribA. 1 hit.

    Sequencei

    Sequence statusi: Complete.

    P0A7I7-1 [UniParc]FASTAAdd to basket

    « Hide

            10         20         30         40         50
    MQLKRVAEAK LPTPWGDFLM VGFEELATGH DHVALVYGDI SGHTPVLARV
    60 70 80 90 100
    HSECLTGDAL FSLRCDCGFQ LEAALTQIAE EGRGILLYHR QEGRNIGLLN
    110 120 130 140 150
    KIRAYALQDQ GYDTVEANHQ LGFAADERDF TLCADMFKLL GVNEVRLLTN
    160 170 180 190
    NPKKVEILTE AGINIVERVP LIVGRNPNNE HYLDTKAEKM GHLLNK
    Length:196
    Mass (Da):21,836
    Last modified:June 7, 2005 - v1
    Checksum:iC22FED98F48098DF
    GO

    Sequence databases

    Select the link destinations:
    EMBLi
    GenBanki
    DDBJi
    Links Updated
    X67876 Genomic DNA. Translation: CAA48075.1.
    U00096 Genomic DNA. Translation: AAC74359.1.
    AP009048 Genomic DNA. Translation: BAA14831.1.
    X60293 Genomic DNA. Translation: CAA42835.1.
    PIRiA40654.
    RefSeqiNP_415793.1. NC_000913.3.
    WP_001176295.1. NZ_LN832404.1.

    Genome annotation databases

    EnsemblBacteriaiAAC74359; AAC74359; b1277.
    BAA14831; BAA14831; BAA14831.
    GeneIDi945763.
    KEGGiecj:JW1269.
    eco:b1277.
    PATRICi32117816. VBIEscCol129921_1328.

    Cross-referencesi

    Sequence databases

    Select the link destinations:
    EMBLi
    GenBanki
    DDBJi
    Links Updated
    X67876 Genomic DNA. Translation: CAA48075.1.
    U00096 Genomic DNA. Translation: AAC74359.1.
    AP009048 Genomic DNA. Translation: BAA14831.1.
    X60293 Genomic DNA. Translation: CAA42835.1.
    PIRiA40654.
    RefSeqiNP_415793.1. NC_000913.3.
    WP_001176295.1. NZ_LN832404.1.

    3D structure databases

    Select the link destinations:
    PDBei
    RCSB PDBi
    PDBji
    Links Updated
    EntryMethodResolution (Å)ChainPositionsPDBsum
    2BZ0X-ray2.60A/B1-196[»]
    2BZ1X-ray1.54A1-196[»]
    ProteinModelPortaliP0A7I7.
    SMRiP0A7I7. Positions 1-173.
    ModBaseiSearch...
    MobiDBiSearch...

    Protein-protein interaction databases

    DIPiDIP-36049N.
    IntActiP0A7I7. 2 interactions.
    STRINGi511145.b1277.

    Proteomic databases

    EPDiP0A7I7.
    PaxDbiP0A7I7.
    PRIDEiP0A7I7.

    Protocols and materials databases

    Structural Biology KnowledgebaseSearch...

    Genome annotation databases

    EnsemblBacteriaiAAC74359; AAC74359; b1277.
    BAA14831; BAA14831; BAA14831.
    GeneIDi945763.
    KEGGiecj:JW1269.
    eco:b1277.
    PATRICi32117816. VBIEscCol129921_1328.

    Organism-specific databases

    EchoBASEiEB1307.
    EcoGeneiEG11331. ribA.

    Phylogenomic databases

    eggNOGiENOG4107T1C. Bacteria.
    COG0807. LUCA.
    HOGENOMiHOG000115442.
    InParanoidiP0A7I7.
    KOiK01497.
    OMAiPTPFGVF.
    PhylomeDBiP0A7I7.

    Enzyme and pathway databases

    UniPathwayiUPA00275; UER00400.
    BioCyciEcoCyc:GTP-CYCLOHYDRO-II-MONOMER.
    ECOL316407:JW1269-MONOMER.
    MetaCyc:GTP-CYCLOHYDRO-II-MONOMER.

    Miscellaneous databases

    EvolutionaryTraceiP0A7I7.
    PROiP0A7I7.

    Family and domain databases

    CDDicd00641. GTP_cyclohydro2. 1 hit.
    HAMAPiMF_00179. RibA. 1 hit.
    InterProiIPR032677. GTP_cyclohydro_II.
    IPR000926. RibA.
    [Graphical view]
    PfamiPF00925. GTP_cyclohydro2. 1 hit.
    [Graphical view]
    SUPFAMiSSF142695. SSF142695. 1 hit.
    TIGRFAMsiTIGR00505. ribA. 1 hit.
    ProtoNetiSearch...

    Entry informationi

    Entry nameiRIBA_ECOLI
    AccessioniPrimary (citable) accession number: P0A7I7
    Secondary accession number(s): P25523, P78147
    Entry historyi
    Integrated into UniProtKB/Swiss-Prot: June 7, 2005
    Last sequence update: June 7, 2005
    Last modified: September 7, 2016
    This is version 91 of the entry and version 1 of the sequence. [Complete history]
    Entry statusiReviewed (UniProtKB/Swiss-Prot)
    Annotation programProkaryotic Protein Annotation Program

    Miscellaneousi

    Miscellaneous

    Catalyzes the formation of GMP as minor product, with concomitant release of pyrophosphate. Release of pyrophosphate requires magnesium ions.

    Keywords - Technical termi

    3D-structure, Complete proteome, Direct protein sequencing, Reference proteome

    Documents

    1. Escherichia coli
      Escherichia coli (strain K12): entries and cross-references to EcoGene
    2. PATHWAY comments
      Index of metabolic and biosynthesis pathways
    3. PDB cross-references
      Index of Protein Data Bank (PDB) cross-references
    4. SIMILARITY comments
      Index of protein domains and families

    Similar proteinsi

    Links to similar proteins from the UniProt Reference Clusters (UniRef) at 100%, 90% and 50% sequence identity:
    100%UniRef100 combines identical sequences and sub-fragments with 11 or more residues from any organism into one UniRef entry.
    90%UniRef90 is built by clustering UniRef100 sequences that have at least 90% sequence identity to, and 80% overlap with, the longest sequence (a.k.a seed sequence).
    50%UniRef50 is built by clustering UniRef90 seed sequences that have at least 50% sequence identity to, and 80% overlap with, the longest sequence in the cluster.