mazF2 Family assigned · medium auto-curated
H37Rv Rv0659c · MTBC0 mtbc0_000697 ·
102 aa · 758771–759079 (-) ·
RefSeq NP_215173.1
Annotation: from legacy to revised
| Legacy (H37Rv / Mycobrowser) | toxin MazF2 |
|---|---|
| MTBC0 PGAP re-annotation | type II toxin-antitoxin system PemK/MazF family toxin |
| Revised (this work) | Type II toxin-antitoxin system PemK/MazF family toxin. Pfam: PemK_toxin (PF02452.24). |
Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.
Curated reference (UniProt)
| UniProt |
P9WII1
SwissProt · reviewed
· Evidence at protein level
|
|---|---|
| UniProt name | Probable endoribonuclease MazF2 |
| EC (curated) |
EC 3.1.-.-
|
| Curated function | Toxic component of a type II toxin-antitoxin (TA) system. Upon expression in E.coli partially inhibits cell growth after one cell generation. Its cognate antitoxin is MazE2. Probably an endoribonuclease (By similarity). |
Functional vocabulary (eggNOG-mapper, orthology transfer)
| COG category |
T Signal transduction mechanisms
|
|---|---|
| eggNOG description | Toxic component of a toxin-antitoxin (TA) module |
| Orthologous group | COG2337 |
| KEGG orthology |
K07171
|
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 | 0.755 · relaxed/neutral |
|---|---|
| Polymorphic sites (≥ 0.1% of strains) | 1 synonymous, 1 missense, 1 nonsense, 0 frameshift |
| Disruption | 1 distinct premature-stop/frameshift site(s); most common in 0.74% of strains (1074) · clonal |
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 |
|---|---|---|---|---|
PemK_toxin | PF02452.24 | 1.3e-12 | 3–98 | PemK-like, MazF-like toxin of type II toxin-antitoxin system |
Functional interaction network (STRING v12, guilt-by-association)
Closest characterised functional partner: mazE2 (antitoxin MazE2), high confidence from genomic context alone (score 903 excluding text-mining).
| Partner | Product | Score | No text-mining | Channels (≥400) |
|---|---|---|---|---|
Rv0660c mazE2 |
antitoxin MazE2 | 903 | 903 ctx | neighborhood:881 |
Rv1246c relE |
toxin RelE | 755 | 644 ctx | cooccurence:633 |
Rv1247c relB |
antitoxin RelB | 665 | 642 ctx | cooccurence:635 |
Rv2865 relF |
antitoxin RelF | 674 | 634 ctx | cooccurence:627 |
Rv1991A mazE6 |
antitoxin MazE6 | 669 | 607 | experimental:434 |
Rv2801A mazE9 |
antitoxin MazE9 | 629 | 579 | |
Rv2866 relG |
toxin RelG | 639 | 576 ctx | cooccurence:564 |
Rv0665 vapC8 |
ribonuclease VapC8 | 536 | 535 | |
Rv0661c vapC7 |
ribonuclease VapC7 | 526 | 525 ctx | neighborhood:524 |
Rv0662c vapB7 |
antitoxin VapB7 | 525 | 525 ctx | neighborhood:524 |
Rv0743c hyp |
hypothetical protein | 477 | 477 ctx | cooccurence:477 |
Rv0595c vapC4 |
ribonuclease VapC4 | 476 | 475 ctx | cooccurence:470 |
Rv0582 vapC26 |
ribonuclease VapC26 | 461 | 461 ctx | cooccurence:456 |
Rv0658c |
integral membrane protein | 443 | 444 ctx | neighborhood:436 |
Rv3095 |
HTH-type transcriptional regulator | 421 | 422 | coexpression:422 |
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: toxin MazF2
- MTBC0 PGAP product: type II toxin-antitoxin system PemK/MazF family toxin
- Pfam (hmmscan --cut_ga): PemK_toxin PF02452.24 (E=1e-12)
- (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_215173.1)
- Domains: Pfam-A via hmmscan --cut_ga — PemK_toxin (PF02452.24)
- 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
COG2337 - Curated reference: UniProt P9WII1 (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 —
25 functional partner(s); context anchor
mazE2 - Primary literature: none located yet; annotation rests on the domain/homology sources above.
Ancestral MTBC0 protein sequence
>mtbc0_000697|Rv0659c|mazF2 MRRGELWFAATPGGDRPVLVLTRDPVADRIGAVVVVALTRTRRGLVSELELTAVENRVPSDCVVNFDNIHTLPRTAFRRRITRLSPARLHEACQTLRASTGC