pyrG Resolved · high auto-curated

H37Rv Rv1699 · MTBC0 mtbc0_001807 · 586 aa · 1935844–1937604 (+) · RefSeq NP_216215.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)CTP synthase
MTBC0 PGAP re-annotationCTP synthase
Revised (this work)CTP synthase. Pfam: CTP_synth_N (PF06418.21), GATase (PF00117.35), Peptidase_C26 (PF07722.20).

Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.

Curated reference (UniProt)

UniProt P9WHK7 SwissProt · reviewed · Evidence at protein level
UniProt nameCTP synthase
EC (curated) EC 6.3.4.2
Curated functionCatalyzes the ATP-dependent amination of UTP to CTP with either L-glutamine or ammonia as the source of nitrogen. Is essential for M.tuberculosis growth in vitro and ex vivo. Regulates intracellular CTP levels through interactions with the four ribonucleotide triphosphates (By similarity).

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category F Nucleotide transport and metabolism
Preferred namepyrG
eggNOG descriptionCatalyzes 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
Orthologous groupCOG0504
EC number EC 6.3.4.2
KEGG orthology K01937
KEGG pathways map00240, map01100
KEGG modules M00052
Gene Ontology (8) GO:0005575, GO:0005623, GO:0005886, GO:0008150, GO:0016020, GO:0040007, GO:0044464, GO:0071944

Orthology-based transfer (eggNOG 5.0.2, diamond). EC/KO/GO/CAZy are computed annotations, not manual curation; cross-check against the primary literature before treating a specific reaction as established.

Conservation & selection (intra-MTBC, 145 209 strains)

pN/pS 0.336 · purifying
Polymorphic sites (≥ 0.1% of strains) 6 synonymous, 6 missense, 0 nonsense, 0 frameshift

pN/pS from segregating SNPs (singletons removed) normalised by possible sites. Low pN/pS = purifying selection (a strong signal that a "hypothetical" is a real, constrained gene). A high pN/pS is ambiguous: relaxed constraint or positive selection (drug resistance, antigenic variation) inflate it; e.g. rpoB/katG/pncA score high here for resistance, not loss of function. A clonal disruption (one allele over a clade) suggests lineage pseudogenisation; a convergent one (many independent alleles) is typical of resistance loss-of-function.

Domains (Pfam, hmmscan --cut_ga)

PfamAccessioni-EvalueResiduesDescription
CTP_synth_NPF06418.21 5.9e-12010–278 CTP synthase N-terminus
GATasePF00117.35 5.8e-31313–542 Glutamine amidotransferase class-I
Peptidase_C26PF07722.20 1.5e-05379–526 Peptidase C26

Functional interaction network (STRING v12, guilt-by-association)

Closest characterised functional partner: Rv1700 (NUDIX hydrolase), high confidence from genomic context alone (score 983 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv1700 NUDIX hydrolase 996 983 ctx neighborhood:882 coexpression:862 textmining:817
Rv3396c guaA GMP synthase 981 961 coexpression:920 textmining:554
Rv1701 xerD tyrosine recombinase XerD 990 932 ctx neighborhood:882 coexpression:449 textmining:860
Rv2445c ndkA nucleoside diphosphate kinase 940 922 database:900
Rv0321 dcd deoxycytidine triphosphate deaminase 927 920 database:900
Rv0719 rplF 50S ribosomal protein L6 940 878 coexpression:417 experimental:799 textmining:533
Rv0703 rplW 50S ribosomal protein L23 887 870 coexpression:414 experimental:788
Rv0716 rplE 50S ribosomal protein L5 934 868 coexpression:418 experimental:782 textmining:523
Rv0722 rpmD 50S ribosomal protein L30 869 868 coexpression:424 experimental:781
Rv3443c rplM 50S ribosomal protein L13 917 836 coexpression:499 experimental:684 textmining:518
Rv0720 rplR 50S ribosomal protein L18 871 833 experimental:766
Rv0715 rplX 50S ribosomal protein L24 828 822 experimental:738
Rv0651 rplJ 50S ribosomal protein L10 841 819 coexpression:704 experimental:414
Rv0714 rplN 50S ribosomal protein L14 920 816 experimental:766 textmining:586
Rv2890c rpsB 30S ribosomal protein S2 905 814 coexpression:773 textmining:514

STRING combines evidence channels (neighborhood, fusion, cooccurrence, coexpression, experimental, database, text-mining) into a 0–1000 score. The ctx badge marks edges carried by the genomic-context channels (conserved neighborhood, fusion, phylogenetic co-occurrence), which are independent of orthology and structure and the strongest signal for an unknown gene. The no text-mining column recomputes the score from data alone, so a link that does not depend on the literature is visible. Association is a function hypothesis, not proof: corroborate with the operon context and the primary literature before assigning a function.

Evidence

  • Legacy H37Rv annotation: CTP synthase
  • MTBC0 PGAP product: CTP synthase
  • Pfam (hmmscan --cut_ga): CTP_synth_N PF06418.21 (E=6e-120), GATase PF00117.35 (E=6e-31), Peptidase_C26 PF07722.20 (E=2e-05)
  • (auto-curated by rules from PGAP + Pfam + Foldseek; not hand-reviewed)

Sources

  • Ancestral sequence & coordinates: Harrison LB et al. (2024), An imputed ancestral reference genome for the MTBC, doi:10.1101/2023.09.07.556366
  • Product annotation: NCBI PGAP on MTBC0; legacy from H37Rv NC_000962.3 (RefSeq NP_216215.1)
  • Domains: Pfam-A via hmmscan --cut_ga — CTP_synth_N (PF06418.21), GATase (PF00117.35), Peptidase_C26 (PF07722.20)
  • Sequence-level signal: ESM Atlas (EvolutionaryScale × BioHub) — exploratory
  • Controlled vocabulary: eggNOG-mapper 2.1.12 (Cantalapiedra et al. 2021, doi:10.1093/molbev/msab293), eggNOG 5.0 DB (Huerta-Cepas et al. 2019) — OG COG0504
  • Curated reference: UniProt P9WHK7 (SwissProt, reviewed; Evidence at protein level)
  • Intra-MTBC selection: pN/pS and disruption from SPDI variants of 145 209 MTBC strains (this work, local collection vs H37Rv NC_000962.3)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 175 functional partner(s); context anchor Rv1700
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_001807|Rv1699|pyrG
MRKHPQTATKHLFVSGGVASSLGKGLTASSLGQLLTARGLHVTMQKLDPYLNVDPGTMNPFQHGEVFVTEDGAETDLDVGHYERFLDRNLPGSANVTTGQVYSTVIAKERRGEYLGDTVQVIPHITDEIKRRILAMAQPDADGNRPDVVITEIGGTVGDIESQPFLEAARQVRHYLGREDVFFLHVSLVPYLAPSGELKTKPTQHSVAALRSIGITPDALILRCDRDVPEALKNKIALMCDVDIDGVISTPDAPSIYDIPKVLHREELDAFVVRRLNLPFRDVDWTEWDDLLRRVHEPHETVRIALVGKYVELSDAYLSVAEALRAGGFKHRAKVEICWVASDGCETTSGAAAALGDVHGVLIPGGFGIRGIEGKIGAIAYARARGLPVLGLCLGLQCIVIEAARSVGLTNANSAEFDPDTPDPVIATMPDQEEIVAGEADLGGTMRLGSYPAVLEPDSVVAQAYQTTQVSERHRHRYEVNNAYRDKIAESGLRFSGTSPDGHLVEFVEYPPDRHPFVVGTQAHPELKSRPTRPHPLFVAFVGAAIDYKAGELLPVEIPEIPEHTPNGSSHRDGVGQPLPEPASRG