mbtI Resolved · high auto-curated
H37Rv Rv2386c · MTBC0 - ·
450 aa · 2678653–2680005 (-) ·
RefSeq YP_177877.1
Annotation: from legacy to revised
| Legacy (H37Rv / Mycobrowser) | salicylate synthase |
|---|---|
| MTBC0 PGAP re-annotation | — |
| Revised (this work) | Salicylate synthase. Pfam: Chorismate_bind (PF00425.25). |
Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.
Annotated on the H37Rv protein: this gene has no 1:1 ancestral MTBC0 anchor (PE/PPE, paralogue, IS element, or otherwise unanchored CDS).
Curated reference (UniProt)
| UniProt |
P9WFX1
SwissProt · reviewed
· Evidence at protein level
|
|---|---|
| UniProt name | Salicylate synthase |
| EC (curated) |
EC 4.2.99.21, EC 5.4.4.2, EC 5.4.99.5
|
| Curated function | Involved in the incorporation of salicylate into the virulence-conferring salicylate-based siderophore mycobactin. Catalyzes the initial conversion of chorismate to yield the intermediate isochorismate (isochorismate synthase activity), and the subsequent elimination of the enolpyruvyl side chain to give salicylate (isochorismate pyruvate-lyase activity). In the absence of magnesium, MbtI displays a chorismate mutase activity and converts chorismate to prephenate. |
Functional vocabulary (eggNOG-mapper, orthology transfer)
| COG category |
H Coenzyme transport and metabolismQ Secondary metabolites biosynthesis, transport and catabolism
|
|---|---|
| Preferred name | mbtI |
| eggNOG description | conversion of chorismate to |
| Orthologous group | COG1169 |
| EC number |
EC 4.2.99.21, EC 5.4.4.2
|
| KEGG orthology |
K04781
|
| KEGG pathways |
map01053, map01110, map01130
|
| Gene Ontology (146) |
GO:0000162, GO:0000287, GO:0003674, GO:0003824, GO:0004049, GO:0004106, GO:0005488, GO:0005575, GO:0005622, GO:0005623, GO:0005737, GO:0005886 +134 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 | 0.727 · relaxed/neutral |
|---|---|
| Polymorphic sites (≥ 0.1% of strains) | 2 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 |
|---|---|---|---|---|
Chorismate_bind | PF00425.25 | 2.4e-69 | 185–438 | chorismate binding enzyme |
Functional interaction network (STRING v12, guilt-by-association)
Closest characterised functional partner: trpG (anthranilate synthase component II), high confidence from genomic context alone (score 993 excluding text-mining).
| Partner | Product | Score | No text-mining | Channels (≥400) |
|---|---|---|---|---|
Rv0013 trpG |
anthranilate synthase component II | 996 | 993 ctx | fusion:529 cooccurence:770 coexpression:694 experimental:788 textmining:479 |
Rv2192c trpD |
anthranilate phosphoribosyltransferase | 991 | 984 ctx | cooccurence:762 coexpression:694 experimental:778 textmining:506 |
Rv2384 mbtA |
2,3-dihydroxybenzoate-AMP ligase | 998 | 971 ctx | fusion:838 coexpression:810 textmining:946 |
Rv1611 trpC |
indole-3-glycerol phosphate synthase | 973 | 957 ctx | cooccurence:766 coexpression:646 experimental:461 textmining:416 |
Rv2383c mbtB |
phenyloxazoline synthase | 996 | 932 | coexpression:866 textmining:946 |
Rv3215 entC |
isochorismate synthase | 942 | 929 | database:900 |
Rv1612 trpB |
tryptophan synthase subunit beta | 953 | 925 ctx | cooccurence:737 coexpression:691 textmining:411 |
Rv1613 trpA |
tryptophan synthase subunit alpha | 958 | 922 ctx | cooccurence:761 coexpression:648 textmining:487 |
Rv2540c aroF |
chorismate synthase | 944 | 910 ctx | cooccurence:441 database:800 textmining:410 |
Rv2552c aroE |
shikimate 5-dehydrogenase | 902 | 865 | database:800 |
Rv1609 trpE |
anthranilate synthase component I | 872 | 857 | database:800 |
Rv3402c hyp |
hypothetical protein | 913 | 831 | coexpression:831 textmining:510 |
Rv2382c mbtC |
polyketide synthetase | 978 | 825 | coexpression:819 textmining:880 |
Rv0948c |
chorismate mutase | 836 | 811 | database:800 |
Rv1885c |
chorismate mutase | 835 | 811 | database:800 |
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
- Annotation from H37Rv (no MTBC0 1:1 anchor; H37Rv protein used): salicylate synthase
- Pfam (hmmscan --cut_ga): Chorismate_bind PF00425.25 (E=2e-69)
- (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 YP_177877.1)
- Domains: Pfam-A via hmmscan --cut_ga — Chorismate_bind (PF00425.25)
- 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
COG1169 - Curated reference: UniProt P9WFX1 (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 —
41 functional partner(s); context anchor
trpG - Primary literature: none located yet; annotation rests on the domain/homology sources above.
Ancestral MTBC0 protein sequence
>H37Rv|Rv2386c|mbtI MSELSVATGAVSTASSSIPMPAGVNPADLAAELAAVVTESVDEDYLLYECDGQWVLAAGVQAMVELDSDELRVIRDGVTRRQQWSGRPGAALGEAVDRLLLETDQAFGWVAFEFGVHRYGLQQRLAPHTPLARVFSPRTRIMVSEKEIRLFDAGIRHREAIDRLLATGVREVPQSRSVDVSDDPSGFRRRVAVAVDEIAAGRYHKVILSRCVEVPFAIDFPLTYRLGRRHNTPVRSFLLQLGGIRALGYSPELVTAVRADGVVITEPLAGTRALGRGPAIDRLARDDLESNSKEIVEHAISVRSSLEEITDIAEPGSAAVIDFMTVRERGSVQHLGSTIRARLDPSSDRMAALEALFPAVTASGIPKAAGVEAIFRLDECPRGLYSGAVVMLSADGGLDAALTLRAAYQVGGRTWLRAGAGIIEESEPEREFEETCEKLSTLTPYLVARQ