Rv2181 Resolved · high auto-curated
H37Rv Rv2181 · MTBC0 mtbc0_002316 ·
427 aa · 2469309–2470592 (+) ·
RefSeq NP_216697.1
Annotation: from legacy to revised
| Legacy (H37Rv / Mycobrowser) | alpha-(1-2)-phosphatidylinositol mannoside mannosyltransferase |
|---|---|
| MTBC0 PGAP re-annotation | alpha-(1-2)-phosphatidylinositol mannoside mannosyltransferase |
| Revised (this work) | Alpha-(1-2)-phosphatidylinositol mannoside mannosyltransferase. Pfam: GT87 (PF09594.17). |
Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.
Curated reference (UniProt)
| UniProt |
P9WMZ9
SwissProt · reviewed
· Evidence at protein level
|
|---|---|
| UniProt name | Polyprenol-phosphate-mannose-dependent alpha-(1-2)-phosphatidylinositol mannoside mannosyltransferase |
| EC (curated) |
EC 2.4.1.-
|
| Curated function | Responsible for the addition of alpha-(1-2) mannose branches to the linear mannan core on the biosynthetic pathway to mature lipoarabinomannan (LAM). |
Functional vocabulary (eggNOG-mapper, orthology transfer)
| COG category |
S Function unknown
|
|---|---|
| eggNOG description | phosphatidylinositol metabolic process |
| Orthologous group | COG5650 |
| KEGG orthology |
K13671
|
| CAZy family |
GT87
|
| Gene Ontology (28) |
GO:0000026, GO:0000030, GO:0003674, GO:0003824, GO:0006629, GO:0006643, GO:0006664, GO:0008150, GO:0008152, GO:0008610, GO:0009058, GO:0009247 +16 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 | 1.124 · relaxed/neutral |
|---|---|
| Polymorphic sites (≥ 0.1% of strains) | 1 synonymous, 3 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 |
|---|---|---|---|---|
GT87 | PF09594.17 | 1.0e-59 | 80–324 | Glycosyltransferase family 87 |
Functional interaction network (STRING v12, guilt-by-association)
Closest characterised functional partner: Rv2180c (integral membrane protein), high confidence from genomic context alone (score 786 excluding text-mining).
| Partner | Product | Score | No text-mining | Channels (≥400) |
|---|---|---|---|---|
Rv2180c |
integral membrane protein | 785 | 786 ctx | neighborhood:783 |
Rv2179c |
3'-5' exoribonuclease | 805 | 776 ctx | neighborhood:775 |
Rv3912 rsmA |
anti-sigma-M factor RsmA | 730 | 730 ctx | cooccurence:708 |
Rv2178c aroG |
phospho-2-dehydro-3-deoxyheptonate aldolase AroG | 715 | 715 ctx | neighborhood:714 |
Rv0236c aftD |
alpha-(1->3)-arabinofuranosyltransferase | 887 | 700 ctx | cooccurence:532 textmining:639 |
Rv0955 |
integral membrane protein | 669 | 670 ctx | cooccurence:665 |
Rv3869 eccB1 |
ESX-1 secretion system protein EccB | 668 | 656 ctx | cooccurence:481 |
Rv3604c |
transmembrane protein | 641 | 641 ctx | cooccurence:640 |
Rv0048c |
membrane protein | 598 | 584 | |
Rv0204c |
transmembrane protein | 575 | 575 ctx | cooccurence:567 |
Rv3895c eccB2 |
ESX-2 secretion system protein EccB | 579 | 564 | |
Rv0051 |
transmembrane protein | 601 | 555 ctx | cooccurence:552 |
Rv1057 hyp |
hypothetical protein | 556 | 534 ctx | cooccurence:532 |
Rv3455c truA |
tRNA pseudouridine synthase A | 548 | 526 | coexpression:487 |
Rv3911 sigM |
ECF RNA polymerase sigma factor SigM | 495 | 495 |
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: alpha-(1-2)-phosphatidylinositol mannoside mannosyltransferase
- MTBC0 PGAP product: alpha-(1-2)-phosphatidylinositol mannoside mannosyltransferase
- Pfam (hmmscan --cut_ga): GT87 PF09594.17 (E=1e-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_216697.1)
- Domains: Pfam-A via hmmscan --cut_ga — GT87 (PF09594.17)
- 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
COG5650 - Curated reference: UniProt P9WMZ9 (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 —
69 functional partner(s); context anchor
Rv2180c - Primary literature: none located yet; annotation rests on the domain/homology sources above.
Ancestral MTBC0 protein sequence
>mtbc0_002316|Rv2181| MSAWRAPEVGSRLGRRVLWCLLWLLAGVALGYVAWRLFGHTPYRIDIDIYQMGARAWLDGRPLYGGGVLFHTPIGLNLPFTYPPLAAVLFSPFAWLQMPAASVAITVLTLVLLIASTAIVLTGLDAWPTSRLVPAPARLRRLWLAVLIVAPATIWLEPISSNFAFGQINVVLMTLVIVDCFPRRTPWPRGLMLGLGIALKLTPAVFLLYFLLRRDGRAALTALASFAVATLLGFVLAWRDSWEYWTHTLHHTDRIGAAALNTDQNIAGALARLTIGDDERFALWVAGSLLVLAATIWAMRRVLRAGEPTLAVICVALFGLVVSPVSWSHHWVWMLPAVLVIGLLGWRRRNVALAMLSLAGVVLMRWTPIDLLPQHRETTAVWWRQLAGMSYVWWALAVIVVAGLTVTARMTPQRSLTRGLTPAPTAS