espG2 Resolved · high auto-curated
H37Rv Rv3889c · MTBC0 mtbc0_004123 ·
276 aa · 4397046–4397876 (-) ·
RefSeq NP_218406.1
Annotation: from legacy to revised
| Legacy (H37Rv / Mycobrowser) | ESX-2 secretion-associated protein EspG2 |
|---|---|
| MTBC0 PGAP re-annotation | type VII secretion system ESX-2 associated protein EspG2 |
| Revised (this work) | Type VII secretion system ESX-2 associated protein EspG2. 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 |
P9WJC9
SwissProt · reviewed
· Inferred from homology
|
|---|---|
| UniProt name | ESX-2 secretion-associated protein EspG2 |
| 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
|
|---|---|
| eggNOG description | EspG family |
| Orthologous group | 2A2YZ |
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) pseudogene candidate
| pN/pS | 0.381 · purifying |
|---|---|
| Polymorphic sites (≥ 0.1% of strains) | 5 synonymous, 5 missense, 0 nonsense, 2 frameshift |
| Disruption | 2 distinct premature-stop/frameshift site(s); most common in 5.43% of strains (7886) · 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 | 1.5e-33 | 5–257 | EspG family |
Functional interaction network (STRING v12, guilt-by-association)
Closest characterised functional partner: esxC (ESAT-6 like protein EsxC), medium confidence from genomic context alone (score 612 excluding text-mining).
| Partner | Product | Score | No text-mining | Channels (≥400) |
|---|---|---|---|---|
Rv3890c esxC |
ESAT-6 like protein EsxC | 860 | 612 ctx | neighborhood:549 textmining:655 |
Rv3888c |
membrane protein | 946 | 606 ctx | neighborhood:590 textmining:870 |
Rv3885c eccE2 |
ESX-2 secretion system protein EccE | 597 | 597 ctx | neighborhood:593 |
Rv3886c mycP2 |
membrane-anchored mycosin | 576 | 577 ctx | neighborhood:551 |
Rv3887c eccD2 |
ESX-2 secretion system protein EccD | 942 | 574 ctx | neighborhood:551 textmining:870 |
Rv3891c esxD |
ESAT-6 like protein EsxD | 495 | 495 ctx | neighborhood:479 |
Rv3884c eccA2 |
ESX-2 secretion system protein EccA | 544 | 447 ctx | neighborhood:444 |
Rv1783 eccC5 |
ESX-5 type VII secretion system protein EccC5 | 452 | 78 | textmining:431 |
Rv0994 moeA1 |
molybdopterin molybdenumtransferase 1 | 602 | 46 | textmining:600 |
Rv0438c moeA2 |
molybdopterin molybdenumtransferase | 601 | 44 | textmining:600 |
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-2 secretion-associated protein EspG2
- MTBC0 PGAP product: type VII secretion system ESX-2 associated protein EspG2
- Pfam (hmmscan --cut_ga): ESX-1_EspG PF14011.12 (E=2e-33)
- (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_218406.1)
- 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
2A2YZ - Curated reference: UniProt P9WJC9 (SwissProt, reviewed; Inferred from homology)
- 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 —
10 functional partner(s); context anchor
esxC - Primary literature: none located yet; annotation rests on the domain/homology sources above.
Ancestral MTBC0 protein sequence
>mtbc0_004123|Rv3889c|espG2 MLTTTVDGLWVLQAVTGVEQTCPELGLRPLLPRLDTAERALRHPVAAELMAVGALDQAGNADPMVREWLTVLLRRDLGLLVTIGVPGGEPTRAAICRFATWWVVLERHGNLVRLYPAGTASDEAGAGELVVGQVERLCGVAEAAPLRPVTVDADELLHAVRDAGTLRSYLLSQRLDVDQLQMVTMAADPTRSAHATLVALQAGVGPEKSARILVGDSTVAIVDTAAGRICVESVTSGQRRYQVLSPGSRSDIGGAVQRLIRRLPAGDEWYSYRRVV