A9BDD9 · PYRG_PROM4

Function

function

Catalyzes the ATP-dependent amination of UTP to CTP with either L-glutamine or ammonia as the source of nitrogen. Regulates intracellular CTP levels through interactions with the four ribonucleotide triphosphates.

Miscellaneous

CTPSs have evolved a hybrid strategy for distinguishing between UTP and CTP. The overlapping regions of the product feedback inhibitory and substrate sites recognize a common feature in both compounds, the triphosphate moiety. To differentiate isosteric substrate and product pyrimidine rings, an additional pocket far from the expected kinase/ligase catalytic site, specifically recognizes the cytosine and ribose portions of the product inhibitor.

Catalytic activity

Activity regulation

Allosterically activated by GTP, when glutamine is the substrate; GTP has no effect on the reaction when ammonia is the substrate. The allosteric effector GTP functions by stabilizing the protein conformation that binds the tetrahedral intermediate(s) formed during glutamine hydrolysis. Inhibited by the product CTP, via allosteric rather than competitive inhibition.

Pathway

Pyrimidine metabolism; CTP biosynthesis via de novo pathway; CTP from UDP: step 2/2.

Features

Showing features for binding site, active site.

TypeIDPosition(s)Description
Binding site13CTP (UniProtKB | ChEBI); allosteric inhibitor
Binding site13UTP (UniProtKB | ChEBI)
Binding site14-19ATP (UniProtKB | ChEBI)
Binding site71ATP (UniProtKB | ChEBI)
Binding site71Mg2+ (UniProtKB | ChEBI)
Binding site141Mg2+ (UniProtKB | ChEBI)
Binding site148-150CTP (UniProtKB | ChEBI); allosteric inhibitor
Binding site188-193CTP (UniProtKB | ChEBI); allosteric inhibitor
Binding site188-193UTP (UniProtKB | ChEBI)
Binding site224CTP (UniProtKB | ChEBI); allosteric inhibitor
Binding site224UTP (UniProtKB | ChEBI)
Binding site354L-glutamine (UniProtKB | ChEBI)
Active site381Nucleophile; for glutamine hydrolysis
Binding site382-385L-glutamine (UniProtKB | ChEBI)
Binding site405L-glutamine (UniProtKB | ChEBI)
Binding site462L-glutamine (UniProtKB | ChEBI)
Active site507
Active site509

GO annotations

AspectTerm
Cellular Componentcytosol
Molecular FunctionATP binding
Molecular FunctionCTP synthase activity
Molecular Functionglutaminase activity
Molecular Functionidentical protein binding
Molecular Functionmetal ion binding
Biological Process'de novo' CTP biosynthetic process
Biological Processglutamine metabolic process
Biological Processpyrimidine nucleobase biosynthetic process

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    CTP synthase
  • EC number
  • Alternative names
    • Cytidine 5'-triphosphate synthase
    • Cytidine triphosphate synthetase
      (CTP synthetase
      ; CTPS
      )
    • UTP--ammonia ligase

Gene names

    • Name
      pyrG
    • Ordered locus names
      P9211_18211

Organism names

Accessions

  • Primary accession
    A9BDD9

Proteomes

Subcellular Location

PTM/Processing

Features

Showing features for chain.

TypeIDPosition(s)Description
ChainPRO_10001395251-555CTP synthase

Interaction

Subunit

Homotetramer.

Protein-protein interaction databases

Structure

Family & Domains

Features

Showing features for region, domain, compositional bias.

TypeIDPosition(s)Description
Region1-267Amidoligase domain
Domain292-534Glutamine amidotransferase type-1
Region532-555Disordered
Compositional bias535-555Polar residues

Sequence similarities

Belongs to the CTP synthase family.

Keywords

Phylogenomic databases

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    555
  • Mass (Da)
    61,227
  • Last updated
    2008-01-15 v1
  • Checksum
    6812E9D83ED48558
MPKFVFVTGGVVSSIGKGIVAASLGRLLKSRGYNVSILKLDPYLNVDPGTMSPFQHGEVFVTEDGAETDLDLGHYERFTDTALSRLNSVTTGSIYQSVINKERRGDYDGGTVQVIPHITQEIRERIHRVGANSNADVVITEIGGTVGDIESLPFLEAIREFKGDVGKKDIAYIHVTLLPFIGTSGELKTKPTQHSVKELRSIGIQPDLLICRSDRPINDNLKNKISGFCGVNNEAVIPALDADSIYSVPLALKAEGLCKEVLEFLDLTDHECNLEKWQELVHKLRNPGPSVKVAVVGKYVQLNDAYLSVVEALRHACIENDASLDLHWICAEKIEEEGSNDLLTGMDAIVVPGGFGSRGVDGKIAAIQWAREQRVPFLGLCLGMQCAVIEWARNLAGLKEATSFELDQSTPHPVIHLLPEQQDVVDLGGTMRLGVYPCRLQAETMGQKLYGEQVVYERHRHRYEFNNAYRNLFIESGYTISGTSPDGRLVELIELKGHPFFTACQYHPEFLSRPGKPHPLFKGLIAAAQSRLPRSPQEALKQTQINSPNQSKNNP

Features

Showing features for compositional bias.

TypeIDPosition(s)Description
Compositional bias535-555Polar residues

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
CP000878
EMBL· GenBank· DDBJ
ABX09752.1
EMBL· GenBank· DDBJ
Genomic DNA

Genome annotation databases

Similar Proteins

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