purC Resolved · high auto-curated
H37Rv Rv0780 · MTBC0 mtbc0_000829 ·
297 aa · 877767–878660 (+) ·
RefSeq NP_215294.1
Annotation: from legacy to revised
| Legacy (H37Rv / Mycobrowser) | phosphoribosylaminoimidazole-succinocarboxamide synthase |
|---|---|
| MTBC0 PGAP re-annotation | phosphoribosylaminoimidazolesuccinocarboxamide synthase |
| Revised (this work) | Phosphoribosylaminoimidazolesuccinocarboxamide synthase. Pfam: SAICAR_synt (PF01259.25). |
Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.
Curated reference (UniProt)
| UniProt |
P9WHN1
SwissProt · reviewed
· Evidence at protein level
|
|---|---|
| UniProt name | Phosphoribosylaminoimidazole-succinocarboxamide synthase |
| EC (curated) |
EC 6.3.2.6
|
Functional vocabulary (eggNOG-mapper, orthology transfer)
| COG category |
F Nucleotide transport and metabolism
|
|---|---|
| Preferred name | purC |
| eggNOG description | Belongs to the SAICAR synthetase family |
| Orthologous group | COG0152 |
| EC number |
EC 6.3.2.6, EC 6.3.4.13
|
| KEGG orthology |
K01923, K01945
|
| KEGG pathways |
map00230, map01100, map01110, map01130
|
| KEGG modules |
M00048
|
| Gene Ontology (68) |
GO:0003674, GO:0003824, GO:0004639, GO:0005575, GO:0005622, GO:0005623, GO:0005737, GO:0006139, GO:0006163, GO:0006164, GO:0006188, GO:0006189 +56 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 | 1.34 · diversifying/relaxed |
|---|---|
| Polymorphic sites (≥ 0.1% of strains) | 1 synonymous, 4 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)
| Pfam | Accession | i-Evalue | Residues | Description |
|---|---|---|---|---|
SAICAR_synt | PF01259.25 | 2.3e-75 | 11–260 | SAICAR synthetase |
Functional interaction network (STRING v12, guilt-by-association)
Closest characterised functional partner: purD (phosphoribosylamine--glycine ligase), high confidence from genomic context alone (score 994 excluding text-mining).
| Partner | Product | Score | No text-mining | Channels (≥400) |
|---|---|---|---|---|
Rv0772 purD |
phosphoribosylamine--glycine ligase | 998 | 994 ctx | fusion:898 coexpression:857 textmining:732 |
Rv0777 purB |
adenylosuccinate lyase PurB | 997 | 992 | coexpression:857 database:900 textmining:738 |
Rv3275c purE |
5-(carboxyamino)imidazole ribonucleotide mutase | 992 | 991 | coexpression:858 database:900 |
Rv0956 purN |
phosphoribosylglycinamide formyltransferase PurN | 957 | 932 | coexpression:861 textmining:407 |
Rv0957 purH |
bifunctional phosphoribosylaminoimidazolecarboxamide formyltransferase/inosinemonophosphate cyclohydrolase | 982 | 925 | coexpression:859 experimental:420 textmining:772 |
Rv0803 purL |
phosphoribosylformylglycinamidine synthase 2 | 921 | 897 | coexpression:858 |
Rv0809 purM |
phosphoribosylformylglycinamidine cyclo-ligase PurM | 936 | 892 | coexpression:857 textmining:431 |
Rv0808 purF |
amidophosphoribosyltransferase | 916 | 891 | coexpression:857 |
Rv0788 purQ |
phosphoribosylformylglycinamidine synthase | 911 | 884 | coexpression:858 |
Rv0787A purS hyp |
hypothetical protein | 910 | 883 | coexpression:857 |
Rv3276c purK |
5-(carboxyamino)imidazole ribonucleotide synthase | 952 | 869 | coexpression:858 textmining:656 |
Rv0782 ptrBb |
Rv0782, (MTCY369.26), len: 552 aa. Probable ptrBb,second part of protease II, equivalent to C-terminus of NP_302455.1|NC_002677 protease II | 805 | 804 ctx | neighborhood:800 |
Rv0781 ptrBa |
Rv0781, (MTCY369.25), len: 236 aa. Probable ptrBa,first part of protease II, equivalent to N-terminus of NP_302455.1|NC_002677 protease II f | 802 | 802 ctx | neighborhood:800 |
Rv0357c purA |
adenylosuccinate synthetase | 831 | 738 | coexpression:661 |
Rv1832 gcvB |
glycine dehydrogenase | 756 | 725 | coexpression:700 |
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: phosphoribosylaminoimidazole-succinocarboxamide synthase
- MTBC0 PGAP product: phosphoribosylaminoimidazolesuccinocarboxamide synthase
- Pfam (hmmscan --cut_ga): SAICAR_synt PF01259.25 (E=2e-75)
- (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_215294.1)
- Domains: Pfam-A via hmmscan --cut_ga — SAICAR_synt (PF01259.25)
- 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
COG0152 - Curated reference: UniProt P9WHN1 (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 —
59 functional partner(s); context anchor
purD - Primary literature: none located yet; annotation rests on the domain/homology sources above.
Ancestral MTBC0 protein sequence
>mtbc0_000829|Rv0780|purC MRPALSDYQHVASGKVREIYRVDDEHLLLVASDRISAYDYVLDSTIPDKGRVLTAMSAFFFGLVDAPNHLAGPPDDPRIPDEVLGRALVVRRLEMLPVECVARGYLTGSGLLDYQATGKVCGIALPPGLVEASRFATPLFTPATKAALGDHDENISFDRVVEMVGALRANQLRDRTLQTYVQAADHALTRGIIIADTKFEFGIDRHGNLLLADEIFTPDSSRYWPADDYRAGVVQTSFDKQFVRSWLTGSESGWDRGSDRPPPPLPEHIVEATRARYINAYERISELKFDDWIGPGA