octT Resolved · medium auto-curated
H37Rv Rv2418c · MTBC0 mtbc0_002574 ·
247 aa · 2740663–2741406 (-) ·
RefSeq NP_216934.1
Annotation: from legacy to revised
| Legacy (H37Rv / Mycobrowser) | hypothetical protein |
|---|---|
| MTBC0 PGAP re-annotation | diglucosylglycerate octanoyltransferase |
| Revised (this work) | Diglucosylglycerate octanoyltransferase. |
Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.
Curated reference (UniProt)
| UniProt |
P71725
SwissProt · reviewed
· Evidence at protein level
|
|---|---|
| UniProt name | Diglucosylglycerate octanoyltransferase |
| EC (curated) |
EC 2.3.1.273
|
| Curated function | Sugar octanoyltransferase likely involved in the biosynthesis of mycobacterial methylglucose lipopolysaccharide (MGLP). Catalyzes the transfer of an octanoyl group from octanoyl-CoA to the C6 OH of the second glucose in diglucosylglycerate (DGG). DGG is the preferred acceptor, but to a lesser extent, GG (glucosylglycerate) can also be used as substrate. DGG and GG are the two earliest intermediates in MGLP biosynthesis. |
Functional vocabulary (eggNOG-mapper, orthology transfer)
| COG category |
E Amino acid transport and metabolism
|
|---|---|
| Preferred name | octT |
| eggNOG description | Sugar octanoyltransferase likely involved in the biosynthesis of mycobacterial methylglucose lipopolysaccharide (MGLP). Catalyzes the transfer of an octanoyl group from octanoyl- CoA to the C6 OH of the second glucose in diglucosylglycerate (DGG) |
| Orthologous group | COG2755 |
| Gene Ontology (25) |
GO:0003674, GO:0003824, GO:0005575, GO:0005623, GO:0005886, GO:0008150, GO:0008374, GO:0009987, GO:0016020, GO:0016043, GO:0016414, GO:0016415 +13 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 | 0.0 · strong purifying |
|---|---|
| Polymorphic sites (≥ 0.1% of strains) | 2 synonymous, 0 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)
No Pfam-A domain above the gathering threshold (or not yet scanned).
Functional interaction network (STRING v12, guilt-by-association)
Closest characterised functional partner: gpgP (glucosyl-3-phosphoglycerate phosphatase), high confidence from genomic context alone (score 901 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.
| Partner | Product | Score | No text-mining | Channels (≥400) |
|---|---|---|---|---|
Rv2419c gpgP |
glucosyl-3-phosphoglycerate phosphatase | 982 | 901 ctx | neighborhood:882 textmining:828 |
Rv2420c rsfS hyp |
hypothetical protein | 889 | 889 ctx | neighborhood:882 |
Rv2421c nadD |
nicotinate-nucleotide adenylyltransferase | 887 | 887 ctx | neighborhood:882 |
Rv2417c |
DegV domain-containing protein | 973 | 797 ctx | neighborhood:786 textmining:875 |
Rv2186c hyp |
hypothetical protein | 778 | 778 ctx | cooccurence:772 |
Rv2695 hyp |
hypothetical protein | 779 | 771 ctx | cooccurence:764 |
Rv3415c hyp |
hypothetical protein | 771 | 771 ctx | cooccurence:770 |
Rv3031 |
1,4-alpha-glucan-branching protein | 907 | 761 ctx | cooccurence:760 textmining:627 |
Rv3212 hyp |
hypothetical protein | 752 | 753 ctx | cooccurence:736 |
Rv1109c hyp |
hypothetical protein | 752 | 752 ctx | cooccurence:752 |
Rv0383c ttfA hyp |
hypothetical protein | 750 | 750 ctx | cooccurence:750 |
Rv2732c |
transmembrane protein | 749 | 749 ctx | cooccurence:742 |
Rv3438 hyp |
hypothetical protein | 750 | 739 ctx | cooccurence:737 |
Rv3034c |
acetyltransferase | 945 | 731 ctx | cooccurence:721 textmining:807 |
Rv3311 hyp |
hypothetical protein | 730 | 730 ctx | cooccurence:727 |
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: hypothetical protein
- MTBC0 PGAP product: diglucosylglycerate octanoyltransferase
- (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_216934.1)
- Domains: Pfam-A via hmmscan --cut_ga — none above threshold
- 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
COG2755 - Curated reference: UniProt P71725 (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 —
107 functional partner(s); context anchor
gpgP - Primary literature: none located yet; annotation rests on the domain/homology sources above.
Ancestral MTBC0 protein sequence
>mtbc0_002574|Rv2418c|octT MSSRRGRRPALLVFADSLAYYGPTGGLPADDPRIWPNIVASQLDWDLELIGRIGWTCRDVWWAATQDPRAWAALPRAGAVIFATGGMDSLPSVLPTALRELIRYVRPSWLRRWVRDGYAWVQPRLSPVARAALPPHLTAEYLEKTRGAIDFNRPGIPIIASLPSVHIAETYGKAHHGRAGTVAAITEWAQHHDIPLVDLKAAVAEQILSGYGNRDGIHWNFEAHQAVAELMLKALAEAGVPNEKSRG