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HAMAP rule MF_01227

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General rule information [?]

Accession MF_01227
Dates 20-SEP-2002 (Created)
1-JUN-2023 (Last updated, Version 37)
Name PyrG
Scope(s) Bacteria
Template(s) P0A7E5 (PYRG_ECOLI); P28595 (PYRG_AZOBR); Q59321 (PYRG_CHLTR); O87761 (PYRG_LACLM); P9WHK7 (PYRG_MYCTU); Q5SIA8 (PYRG_THET8); Q980S6 (PYRG_SACS2); [ Recover all ]
Triggered by HAMAP; MF_01227 (Get profile general information and statistics)

Propagated annotation [?]

Identifier, protein and gene names [?]

Identifier PYRG
Protein name RecName: Full=CTP synthase;
AltName: Full=Cytidine 5'-triphosphate synthase;
AltName: Full=Cytidine triphosphate synthetase;
                 Short=CTP synthetase;
AltName: Full=UTP--ammonia ligase;
Gene name Name=pyrG;

Comments [?]

FUNCTIONCatalyzes 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.
CATALYTIC ACTIVITY Reaction=ATP + H2O + L-glutamine + UTP = ADP + CTP + 2 H(+) + L- glutamate + phosphate; Xref=Rhea:RHEA:26426, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:29985, ChEBI:CHEBI:30616, ChEBI:CHEBI:37563, ChEBI:CHEBI:43474, ChEBI:CHEBI:46398, ChEBI:CHEBI:58359, ChEBI:CHEBI:456216; EC=;
CATALYTIC ACTIVITY Reaction=H2O + L-glutamine = L-glutamate + NH4(+); Xref=Rhea:RHEA:15889, ChEBI:CHEBI:15377, ChEBI:CHEBI:28938, ChEBI:CHEBI:29985, ChEBI:CHEBI:58359;
CATALYTIC ACTIVITY Reaction=ATP + NH4(+) + UTP = ADP + CTP + 2 H(+) + phosphate; Xref=Rhea:RHEA:16597, ChEBI:CHEBI:15378, ChEBI:CHEBI:28938, ChEBI:CHEBI:30616, ChEBI:CHEBI:37563, ChEBI:CHEBI:43474, ChEBI:CHEBI:46398, ChEBI:CHEBI:456216;
ACTIVITY REGULATIONAllosterically 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.
PATHWAYPyrimidine metabolism; CTP biosynthesis via de novo pathway; CTP from UDP: step 2/2.
MISCELLANEOUSCTPSs 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.
SIMILARITYBelongs to the CTP synthase family.

Keywords [?]

Gene Ontology [?]

GO:0003883; Molecular function:CTP synthase activity
GO:0006221; Biological process:pyrimidine nucleotide biosynthetic process

Cross-references [?]

Pfam PF06418; CTP_synth_N; 1;
Pfam PF00117; GATase; 1;
NCBIfam TIGR00337; PyrG; 1;

Features [?]

Key From To Description Tag Condition FTGroup
BINDING 15 20 /ligand="ATP"
BINDING 147 149 /ligand="CTP"
/ligand_note="allosteric inhibitor"
BINDING 187 192 /ligand="CTP"
/ligand_note="allosteric inhibitor"
BINDING 187 192 /ligand="UTP"
BINDING 239 241 /ligand="ATP"
case not <FT:5>
BINDING 241 241 /ligand="ATP"
end case
REGION Nter 266 /note="Amidoligase domain"
BINDING 380 383 /ligand="L-glutamine"
ACT_SITE 379 379 /note="Nucleophile; for glutamine hydrolysis" C
ACT_SITE 515 515 H
ACT_SITE 517 517 E
BINDING 72 72 /ligand="Mg(2+)"
BINDING 140 140 /ligand="Mg(2+)"
BINDING 14 14 /ligand="CTP"
/ligand_note="allosteric inhibitor"
BINDING 14 14 /ligand="UTP"
BINDING 55 55 /ligand="L-glutamine"
BINDING 72 72 /ligand="ATP"
BINDING 223 223 /ligand="CTP"
/ligand_note="allosteric inhibitor"
BINDING 223 223 /ligand="UTP"
BINDING 352 352 /ligand="L-glutamine"
BINDING 403 403 /ligand="L-glutamine"
BINDING 470 470 /ligand="L-glutamine"

Additional information [?]

Size range 524-608 amino acids
Related rules None
Fusion Nter: None Cter: None
Comments RPE1 type insert in RICPR and weird insertion in TREPA; sequences not shown in alignment. Divergent UREPA; sequence not included in alignment.

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