mbtK Resolved · high auto-curated
H37Rv Rv1347c · MTBC0 mtbc0_001444 ·
210 aa · 1522675–1523307 (-) ·
RefSeq NP_215863.1
Annotation: from legacy to revised
| Legacy (H37Rv / Mycobrowser) | lysine N-acetyltransferase MbtK |
|---|---|
| MTBC0 PGAP re-annotation | lysine N-acyltransferase MbtK |
| Revised (this work) | Lysine N-acyltransferase MbtK. Pfam: Acetyltransf_8 (PF13523.13). |
Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.
Curated reference (UniProt)
| UniProt |
P9WK15
SwissProt · reviewed
· Evidence at protein level
|
|---|---|
| UniProt name | Lysine N-acyltransferase MbtK |
| EC (curated) |
EC 2.3.1.-
|
| Curated function | Acyltransferase required for the direct transfer of medium- to long-chain fatty acyl moieties from a carrier protein (MbtL) on to the epsilon-amino group of lysine residue in the mycobactin core. |
Functional vocabulary (eggNOG-mapper, orthology transfer)
| COG category |
J Translation, ribosomal structure and biogenesis
|
|---|---|
| Preferred name | mbtK |
| eggNOG description | COG1670 Acetyltransferases, including N-acetylases of ribosomal proteins |
| Orthologous group | COG1670 |
| KEGG orthology |
K21992
|
| Gene Ontology (42) |
GO:0003674, GO:0003824, GO:0006518, GO:0006725, GO:0006807, GO:0008150, GO:0008152, GO:0009058, GO:0009237, GO:0009712, GO:0009987, GO:0016289 +30 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 | 0.325 · purifying |
|---|---|
| Polymorphic sites (≥ 0.1% of strains) | 4 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 |
|---|---|---|---|---|
Acetyltransf_8 | PF13523.13 | 1.1e-45 | 51–192 | Acetyltransferase (GNAT) domain |
Functional interaction network (STRING v12, guilt-by-association)
Closest characterised functional partner: mbtG (L-lysine N6-monooxygenase), high confidence from genomic context alone (score 794 excluding text-mining).
| Partner | Product | Score | No text-mining | Channels (≥400) |
|---|---|---|---|---|
Rv3402c hyp |
hypothetical protein | 863 | 816 | coexpression:810 |
Rv2378c mbtG |
L-lysine N6-monooxygenase | 921 | 794 ctx | cooccurence:410 coexpression:583 textmining:635 |
Rv0923c hyp |
hypothetical protein | 575 | 575 ctx | cooccurence:575 |
Rv2925c rnc |
ribonuclease III | 541 | 541 | coexpression:539 |
Rv1348 irtA |
iron ABC transporter ATP-binding protein/permease IrtA | 813 | 504 | textmining:639 |
Rv1349 irtB |
iron ABC transporter ATP-binding protein/permease IrtB | 809 | 492 | textmining:640 |
Rv3073c hyp |
hypothetical protein | 462 | 463 ctx | neighborhood:461 |
Rv0585c |
integral membrane protein | 425 | 425 | |
Rv2380c mbtE |
peptide synthetase | 598 | 424 | |
Rv0779c |
transmembrane protein | 407 | 408 ctx | cooccurence:406 |
Rv2379c mbtF |
peptide synthetase | 704 | 395 | textmining:531 |
Rv2386c mbtI |
salicylate synthase | 590 | 353 | |
Rv2383c mbtB |
phenyloxazoline synthase | 679 | 310 | textmining:555 |
Rv1346 mbtN |
acyl-[acyl-carrier-protein | 779 | 298 | textmining:699 |
Rv2382c mbtC |
polyketide synthetase | 714 | 265 | textmining:627 |
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: lysine N-acetyltransferase MbtK
- MTBC0 PGAP product: lysine N-acyltransferase MbtK
- Pfam (hmmscan --cut_ga): Acetyltransf_8 PF13523.13 (E=1e-45)
- (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_215863.1)
- Domains: Pfam-A via hmmscan --cut_ga — Acetyltransf_8 (PF13523.13)
- 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
COG1670 - Curated reference: UniProt P9WK15 (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 —
21 functional partner(s); context anchor
mbtG - Primary literature: none located yet; annotation rests on the domain/homology sources above.
Ancestral MTBC0 protein sequence
>mtbc0_001444|Rv1347c|mbtK MTKPTSAGQADDALVRLARERFDLPDQVRRLARPPVPSLEPPYGLRVAQLTDAEMLAEWMNRPHLAAAWEYDWPASRWRQHLNAQLEGTYSLPLIGSWHGTDGGYLELYWAAKDLISHYYDADPYDLGLHAAIADLSKVNRGFGPLLLPRIVASVFANEPRCRRIMFDPDHRNTATRRLCEWAGCKFLGEHDTTNRRMALYALEAPTTAA