esxB Family assigned · medium auto-curated
H37Rv Rv3874 · MTBC0 mtbc0_004107 ·
100 aa · 4376484–4376786 (+) ·
RefSeq NP_218391.1
Annotation: from legacy to revised
| Legacy (H37Rv / Mycobrowser) | ESAT-6-like protein EsxB |
|---|---|
| MTBC0 PGAP re-annotation | type VII secretion system ESX-1 WXG100 family target CFP-10 |
| Revised (this work) | Type VII secretion system ESX-1 WXG100 family target CFP-10. Pfam: T7SS_ESX_EspC (PF10824.15), WXG100 (PF06013.19). |
Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.
Curated reference (UniProt)
| UniProt |
P9WNK5
SwissProt · reviewed
· Evidence at protein level
|
|---|---|
| UniProt name | ESAT-6-like protein EsxB |
| Curated function | A secreted protein. Acts as a strong host (human) T-cell antigen. Involved in translocation of bacteria from the host (human) phagolysosome to the host cytoplasm. Might serve as a chaperone to prevent uncontrolled membrane lysis by its partner EsxA; native protein binds poorly to artificial liposomes in the absence or presence of EsxA. EsxA and EsxA-EsxB are cytotoxic to pneumocytes. EsxB (and EsxA-EsxB but not EsxA alone) activates human neutrophils; EsxB transiently induces host (human) intracellular Ca(2+) mobility in a dose-dependent manner, monocytes and lymphocytes do not respond. Neutro. |
Functional vocabulary (eggNOG-mapper, orthology transfer)
| COG category |
S Function unknown
|
|---|---|
| Preferred name | esxB |
| eggNOG description | Belongs to the WXG100 family |
| Orthologous group | COG4842 |
| Gene Ontology (36) |
GO:0002790, GO:0003674, GO:0005488, GO:0005575, GO:0005576, GO:0005618, GO:0005623, GO:0005886, GO:0006810, GO:0008104, GO:0008150, GO:0009306 +24 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 | n/a |
|---|---|
| Polymorphic sites (≥ 0.1% of strains) | 0 synonymous, 1 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 |
|---|---|---|---|---|
T7SS_ESX_EspC | PF10824.15 | 3.4e-05 | 3–95 | Excreted virulence factor EspC, type VII ESX diderm |
WXG100 | PF06013.19 | 2.9e-18 | 4–88 | Proteins of 100 residues with WXG |
Functional interaction network (STRING v12, guilt-by-association)
Closest characterised functional partner: esxA (ESAT-6 protein EsxA), high confidence from genomic context alone (score 1000 excluding text-mining).
| Partner | Product | Score | No text-mining | Channels (≥400) |
|---|---|---|---|---|
Rv3875 esxA |
ESAT-6 protein EsxA | 999 | 1000 ctx | neighborhood:833 coexpression:853 experimental:999 textmining:997 |
Rv3871 eccCb1 |
ESX-1 secretion system protein EccCb | 998 | 992 | experimental:987 textmining:879 |
Rv3870 eccCa1 |
ESX-1 secretion system protein EccCa | 937 | 821 ctx | neighborhood:580 experimental:585 textmining:664 |
Rv1038c esxJ |
ESAT-6 like protein EsxJ | 910 | 813 | coexpression:813 textmining:540 |
Rv1198 esxL |
ESAT-6 like protein EsxL | 901 | 803 | coexpression:803 textmining:521 |
Rv3620c esxW |
ESAT-6 like protein EsxW | 926 | 802 | coexpression:802 textmining:644 |
Rv1197 esxK |
ESAT-6 like protein EsxK | 898 | 802 | coexpression:802 textmining:508 |
Rv2347c esxP |
ESAT-6 like protein EsxP | 927 | 799 | coexpression:799 textmining:653 |
Rv2346c esxO |
ESAT-6 like protein EsxO | 899 | 796 | coexpression:796 textmining:530 |
Rv3873 PPE68 |
PPE family protein PPE68 | 963 | 788 ctx | neighborhood:776 textmining:834 |
Rv1793 esxN |
ESAT-6 like protein EsxN | 916 | 761 | coexpression:761 textmining:664 |
Rv3648c cspA |
cold shock protein A | 782 | 736 | coexpression:733 |
Rv0288 esxH |
ESAT-6-like protein EsxH | 976 | 734 | coexpression:734 textmining:915 |
Rv3619c esxV |
ESAT-6 like protein EsxV | 898 | 731 | coexpression:731 textmining:637 |
Rv3869 eccB1 |
ESX-1 secretion system protein EccB | 843 | 727 ctx | neighborhood:550 textmining:450 |
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: ESAT-6-like protein EsxB
- MTBC0 PGAP product: type VII secretion system ESX-1 WXG100 family target CFP-10
- Pfam (hmmscan --cut_ga): T7SS_ESX_EspC PF10824.15 (E=3e-05), WXG100 PF06013.19 (E=3e-18)
- (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_218391.1)
- Domains: Pfam-A via hmmscan --cut_ga — T7SS_ESX_EspC (PF10824.15), WXG100 (PF06013.19)
- 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
COG4842 - Curated reference: UniProt P9WNK5 (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 —
87 functional partner(s); context anchor
esxA - Primary literature: none located yet; annotation rests on the domain/homology sources above.
Ancestral MTBC0 protein sequence
>mtbc0_004107|Rv3874|esxB MAEMKTDAATLAQEAGNFERISGDLKTQIDQVESTAGSLQGQWRGAAGTAAQAAVVRFQEAANKQKQELDEISTNIRQAGVQYSRADEEQQQALSSQMGF