purN Resolved · high auto-curated

H37Rv Rv0956 · MTBC0 mtbc0_001020 · 215 aa · 1074776–1075423 (+) · RefSeq NP_215471.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)phosphoribosylglycinamide formyltransferase PurN
MTBC0 PGAP re-annotationphosphoribosylglycinamide formyltransferase
Revised (this work)Phosphoribosylglycinamide formyltransferase. Pfam: Formyl_trans_N (PF00551.25).

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

Curated reference (UniProt)

UniProt P9WHM5 SwissProt · reviewed · Evidence at protein level
UniProt namePhosphoribosylglycinamide formyltransferase
EC (curated) EC 2.1.2.2
Curated functionCatalyzes the transfer of a formyl group from 10-formyltetrahydrofolate to 5-phospho-ribosyl-glycinamide (GAR), producing 5-phospho-ribosyl-N-formylglycinamide (FGAR) and tetrahydrofolate.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category F Nucleotide transport and metabolism
Preferred namepurN
eggNOG descriptionCatalyzes the transfer of a formyl group from 10- formyltetrahydrofolate to 5-phospho-ribosyl-glycinamide (GAR), producing 5-phospho-ribosyl-N-formylglycinamide (FGAR) and tetrahydrofolate
Orthologous groupCOG0299
EC number EC 2.1.2.2
KEGG orthology K11175
KEGG pathways map00230, map00670, map01100, map01110, map01130
KEGG modules M00048
Gene Ontology (28) GO:0000287, GO:0003674, GO:0005488, GO:0006082, GO:0006575, GO:0006725, GO:0006732, GO:0006760, GO:0006807, GO:0008150, GO:0008152, GO:0009987 +16 more

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 0.789 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 3 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
Formyl_trans_NPF00551.25 7.8e-4214–191 Formyl transferase

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

Closest characterised functional partner: purD (phosphoribosylamine--glycine ligase), high confidence from genomic context alone (score 1000 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv0772 purD phosphoribosylamine--glycine ligase 999 1000 ctx fusion:900 cooccurence:753 coexpression:858 database:900 textmining:529
Rv0957 purH bifunctional phosphoribosylaminoimidazolecarboxamide formyltransferase/inosinemonophosphate cyclohydrolase 999 1000 ctx neighborhood:882 fusion:899 cooccurence:631 coexpression:860 database:900 textmining:956
Rv0809 purM phosphoribosylformylglycinamidine cyclo-ligase PurM 998 997 ctx fusion:900 cooccurence:755 coexpression:857 textmining:606
Rv0788 purQ phosphoribosylformylglycinamidine synthase 995 992 ctx cooccurence:451 coexpression:857 database:900 textmining:432
Rv0803 purL phosphoribosylformylglycinamidine synthase 2 995 992 ctx cooccurence:443 coexpression:857 database:900 textmining:441
Rv0787A purS hyp hypothetical protein 993 986 coexpression:843 database:900 textmining:576
Rv0808 purF amidophosphoribosyltransferase 975 968 ctx cooccurence:719 coexpression:857
Rv3356c folD bifunctional methylenetetrahydrofolate dehydrogenase/methenyltetrahydrofolate cyclohydrolase 995 962 coexpression:425 database:900 textmining:895
Rv0389 purT phosphoribosylglycinamide formyltransferase PurT 968 959 coexpression:610 database:900
Rv0070c glyA2 serine hydroxymethyltransferase 966 953 coexpression:458 database:900
Rv1093 glyA1 serine hydroxymethyltransferase 966 952 coexpression:453 database:900
Rv3275c purE 5-(carboxyamino)imidazole ribonucleotide mutase 961 949 ctx cooccurence:608 coexpression:859
Rv0780 purC phosphoribosylaminoimidazole-succinocarboxamide synthase 957 932 coexpression:861 textmining:407
Rv0992c 5-formyltetrahydrofolate cyclo-ligase 929 922 database:900
Rv2754c thyX thymidylate synthase ThyX 943 918 database:900

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: phosphoribosylglycinamide formyltransferase PurN
  • MTBC0 PGAP product: phosphoribosylglycinamide formyltransferase
  • Pfam (hmmscan --cut_ga): Formyl_trans_N PF00551.25 (E=8e-42)
  • (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_215471.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Formyl_trans_N (PF00551.25)
  • 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 COG0299
  • Curated reference: UniProt P9WHM5 (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 — 71 functional partner(s); context anchor purD
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_001020|Rv0956|purN
MQEPLRVPPSAPARLVVLASGTGSLLRSLLDAAVGDYPARVVAVGVDRECRAAEIAAEASVPVFTVRLADHPSRDAWDVAITAATAAHEPDLVVSAGFMRILGPQFLSRFYGRTLNTHPALLPAFPGTHGVADALAYGVKVTGATVHLVDAGTDTGPILAQQPVPVLDGDDEETLHERIKVTERRLLVAAVAALATHGVTVVGRTATMGRKVTIG