mptB Resolved · high auto-curated
H37Rv Rv1459c · MTBC0 mtbc0_001561 ·
591 aa · 1654168–1655943 (-) ·
RefSeq NP_215975.1
Annotation: from legacy to revised
| Legacy (H37Rv / Mycobrowser) | alpha-(1->6)-mannopyranosyltransferase |
|---|---|
| MTBC0 PGAP re-annotation | polyprenol phosphomannose-dependent alpha 1%2C6 mannosyltransferase MptB |
| Revised (this work) | Polyprenol phosphomannose-dependent alpha 1%2C6 mannosyltransferase MptB. Pfam: MptA_B_family (PF26314.1), MptB_C (PF27547.1). |
Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.
Curated reference (UniProt)
| UniProt |
O53150
SwissProt · reviewed
· Evidence at protein level
|
|---|---|
| UniProt name | Alpha-(1->6)-mannopyranosyltransferase Rv1459c |
| EC (curated) |
EC 2.4.1.-
|
| Curated function | Catalyzes the addition of alpha-(1->6)-mannose residue. |
Functional vocabulary (eggNOG-mapper, orthology transfer)
| COG category |
S Function unknown
|
|---|---|
| eggNOG description | transferase activity, transferring glycosyl groups |
| Orthologous group | 2BVCQ |
| KEGG orthology |
K14339
|
| 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 | 0.925 · relaxed/neutral |
|---|---|
| Polymorphic sites (≥ 0.1% of strains) | 3 synonymous, 7 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 |
|---|---|---|---|---|
MptA_B_family | PF26314.1 | 9.9e-87 | 38–357 | Alpha-(1->6)-mannopyranosyltransferase family |
MptB_C | PF27547.1 | 4.2e-29 | 406–481 | MptB C-terminal domain |
Functional interaction network (STRING v12, guilt-by-association)
Closest characterised functional partner: Rv1457c (antibiotic ABC transporter permease), high confidence from genomic context alone (score 832 excluding text-mining).
| Partner | Product | Score | No text-mining | Channels (≥400) |
|---|---|---|---|---|
Rv2174 mptA |
alpha(1->6)-mannopyranosyltransferase A | 948 | 928 | database:900 |
Rv1457c |
antibiotic ABC transporter permease | 977 | 832 ctx | neighborhood:772 textmining:870 |
Rv1458c |
antibiotic ABC transporter ATP-binding protein | 906 | 795 ctx | neighborhood:772 textmining:561 |
Rv1456c |
antibiotic ABC transporter permease | 957 | 784 ctx | neighborhood:699 textmining:810 |
Rv1460 sufR |
transcriptional regulator | 780 | 780 ctx | neighborhood:779 |
Rv1462 sufD hyp |
hypothetical protein | 777 | 776 ctx | neighborhood:773 |
Rv1464 csd |
cysteine desulfurase | 777 | 774 ctx | neighborhood:772 |
Rv1463 sufC |
ABC transporter ATP-binding protein | 774 | 774 ctx | neighborhood:773 |
Rv1465 |
nitrogen fixation related protein | 731 | 731 ctx | neighborhood:726 |
Rv0365c hyp |
hypothetical protein | 730 | 730 ctx | cooccurence:730 |
Rv0556 |
transmembrane protein | 729 | 729 ctx | cooccurence:729 |
Rv1466 hyp |
hypothetical protein | 727 | 728 ctx | neighborhood:726 |
Rv3438 hyp |
hypothetical protein | 718 | 718 ctx | cooccurence:715 |
Rv2732c |
transmembrane protein | 697 | 698 ctx | cooccurence:696 |
Rv1632c hyp |
hypothetical protein | 687 | 688 ctx | cooccurence:686 |
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->6)-mannopyranosyltransferase
- MTBC0 PGAP product: polyprenol phosphomannose-dependent alpha 1%2C6 mannosyltransferase MptB
- Pfam (hmmscan --cut_ga): MptA_B_family PF26314.1 (E=1e-86), MptB_C PF27547.1 (E=4e-29)
- (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_215975.1)
- Domains: Pfam-A via hmmscan --cut_ga — MptA_B_family (PF26314.1), MptB_C (PF27547.1)
- 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
2BVCQ - Curated reference: UniProt O53150 (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 —
101 functional partner(s); context anchor
Rv1457c - Primary literature: none located yet; annotation rests on the domain/homology sources above.
Ancestral MTBC0 protein sequence
>mtbc0_001561|Rv1459c|mptB MAARHHTLSWSIASLHGDEQAVGAPLTTTELTALARTRLFGATGTVLMAIGALGAGARPVVQDPTFGVRLLNLPSRIQTVSLTMTTTGAVMMALAWLMLGRFTLGRRRMSRGELDRTLLLWMLPLLIAPPMYSKDVYSYLAQSEIGRDGLDPYRVGPASGLGLGHVFTLSVPSLWRETPAPYGPLFLWIGRGISSLTGENIVAAVLCHRLVVLIGVTLIVWATPRLAQRCGVAEVSALWLGAANPLLIMHLVAGIHNEALMLGLMLTGVEFALRGLDMANTPRPSPETWRLGPATIRASRRPELGASPRAGASRAVKPRPEWGPLAMLLAGSILITLSSQVKLPSLLAMGFVTTVLAYRWGGNLRALLLAAAVMASLTLAIMAILGWASGLGFGWINTLGTANVVRSWMSPPTLLALGTGHVGILLGLGDHTTAVLSLTRAIGVLIITVMVCWLLLAVLRGRLHPIGGLGVALAVTVLLFPVVQPWYLLWAIIPLAAWATRPGFRVAAILATLIVGIFGPTANGDRFALFQIVDATAASAIIVILLIALTYTRLPWRPLAAEQVVTAAESASKTPATRRPTAAPDAYADST