espG3 Resolved · high auto-curated
H37Rv Rv0289 · MTBC0 mtbc0_000308 ·
295 aa · 355443–356330 (+) ·
RefSeq NP_214803.1
Annotation: from legacy to revised
| Legacy (H37Rv / Mycobrowser) | ESX-3 secretion-associated protein EspG3 |
|---|---|
| MTBC0 PGAP re-annotation | type VII secretion system ESX-3 associated protein EspG3 |
| Revised (this work) | Type VII secretion system ESX-3 associated protein EspG3. Pfam: ESX-1_EspG (PF14011.12). |
Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.
Curated reference (UniProt)
| UniProt |
P9WJC7
SwissProt · reviewed
· Evidence at protein level
|
|---|---|
| UniProt name | ESX-3 secretion-associated protein EspG3 |
| Curated function | Specific chaperone for cognate PE/PPE proteins. Plays an important role in preventing aggregation of PE/PPE dimers. |
Functional vocabulary (eggNOG-mapper, orthology transfer)
| COG category |
S Function unknown
|
|---|---|
| Preferred name | espG3 |
| eggNOG description | EspG family |
| Orthologous group | 2A0WB |
| Gene Ontology (2) |
GO:0008150, GO:0040007
|
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 | 0.457 · purifying |
|---|---|
| Polymorphic sites (≥ 0.1% of strains) | 4 synonymous, 5 missense, 0 nonsense, 1 frameshift |
| Disruption | 1 distinct premature-stop/frameshift site(s); most common in 0.46% of strains (664) · clonal |
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 |
|---|---|---|---|---|
ESX-1_EspG | PF14011.12 | 1.8e-59 | 11–269 | EspG family |
Functional interaction network (STRING v12, guilt-by-association)
Closest characterised functional partner: mycP3 (membrane-anchored mycosin MycP), high confidence from genomic context alone (score 970 excluding text-mining).
| Partner | Product | Score | No text-mining | Channels (≥400) |
|---|---|---|---|---|
Rv0291 mycP3 |
membrane-anchored mycosin MycP | 989 | 970 ctx | neighborhood:815 coexpression:845 textmining:667 |
Rv0290 eccD3 |
ESX-3 secretion system protein EccD | 996 | 969 ctx | neighborhood:815 coexpression:841 textmining:878 |
Rv0292 eccE3 |
ESX-3 secretion system protein EccE | 988 | 966 ctx | neighborhood:815 coexpression:822 textmining:678 |
Rv0288 esxH |
ESAT-6-like protein EsxH | 980 | 963 ctx | neighborhood:859 coexpression:751 textmining:484 |
Rv0287 esxG |
ESAT-6 like protein EsxG | 974 | 940 ctx | neighborhood:707 coexpression:802 textmining:595 |
Rv0286 PPE4 |
PPE family protein PPE4 | 954 | 936 ctx | neighborhood:564 coexpression:860 |
Rv0283 eccB3 |
ESX-3 secretion system protein EccB3 | 974 | 926 ctx | neighborhood:734 coexpression:733 textmining:672 |
Rv0282 eccA3 |
ESX-3 secretion system protein EccA | 915 | 845 ctx | neighborhood:767 textmining:473 |
Rv0284 eccC3 |
ESX-3 secretion system protein EccC3 | 916 | 842 ctx | neighborhood:768 textmining:493 |
Rv0285 PE5 |
PE family protein PE5 | 715 | 597 ctx | neighborhood:597 |
Rv0281 |
S-adenosylmethionine-dependent methyltransferase | 426 | 426 | |
Rv0280 PPE3 |
PPE family protein PPE3 | 464 | 333 | |
Rv3020c esxS |
ESAT-6 like protein EsxS | 469 | 168 | |
Rv3019c esxR |
ESAT-6 like protein EsxR | 518 | 145 | textmining:460 |
Rv3874 esxB |
ESAT-6-like protein EsxB | 422 | 83 |
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: ESX-3 secretion-associated protein EspG3
- MTBC0 PGAP product: type VII secretion system ESX-3 associated protein EspG3
- Pfam (hmmscan --cut_ga): ESX-1_EspG PF14011.12 (E=2e-59)
- (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_214803.1)
- Domains: Pfam-A via hmmscan --cut_ga — ESX-1_EspG (PF14011.12)
- 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
2A0WB - Curated reference: UniProt P9WJC7 (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 —
19 functional partner(s); context anchor
mycP3 - Primary literature: none located yet; annotation rests on the domain/homology sources above.
Ancestral MTBC0 protein sequence
>mtbc0_000308|Rv0289|espG3 MDATPNAVELTVDNAWFIAETIGAGTFPWVLAITMPYSDAAQRGAFVDRQRDELTRMGLLSPQGVINPAVADWIKVVCFPDRWLDLRYVGPASADGACELLRGIVALRTGTGKTSNKTGNGVVALRNAQLVTFTAMDIDDPRALVPILGVGLAHRPPARFDEFSLPTRVGARADERLRSGVPLGEVVDYLGIPASARPVVESVFSGPRSYVEIVAGCNRDGRHTTTEVGLSIVDTSAGRVLVSPSRAFDGEWVSTFSPGTPFAIAVAIQTLTACLPDGQWFPGQRVSRDFSTQSS