mapB Resolved · high auto-curated
H37Rv Rv2861c · MTBC0 - ·
285 aa · 3173160–3174017 (-) ·
RefSeq YP_177911.1
Annotation: from legacy to revised
| Legacy (H37Rv / Mycobrowser) | methionine aminopeptidase |
|---|---|
| MTBC0 PGAP re-annotation | — |
| Revised (this work) | Methionine aminopeptidase. Pfam: Peptidase_M24 (PF00557.30). |
Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.
Annotated on the H37Rv protein: this gene has no 1:1 ancestral MTBC0 anchor (PE/PPE, paralogue, IS element, or otherwise unanchored CDS).
Curated reference (UniProt)
| UniProt |
P9WK19
SwissProt · reviewed
· Evidence at protein level
|
|---|---|
| UniProt name | Methionine aminopeptidase 2 |
| EC (curated) |
EC 3.4.11.18
|
| Curated function | Removes the N-terminal methionine from nascent proteins. The N-terminal methionine is often cleaved when the second residue in the primary sequence is small and uncharged (Met-Ala-, Cys, Gly, Pro, Ser, Thr, or Val). Requires deformylation of the N(alpha)-formylated initiator methionine before it can be hydrolyzed. |
Functional vocabulary (eggNOG-mapper, orthology transfer)
| COG category |
E Amino acid transport and metabolism
|
|---|---|
| Preferred name | map |
| eggNOG description | Methionine aminopeptidase |
| Orthologous group | COG0024 |
| EC number |
EC 3.4.11.18
|
| KEGG orthology |
K01265
|
| Gene Ontology (51) |
GO:0000096, GO:0003674, GO:0003824, GO:0004177, GO:0005488, GO:0005506, GO:0006082, GO:0006464, GO:0006508, GO:0006520, GO:0006555, GO:0006790 +39 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 | 0.331 · 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 |
|---|---|---|---|---|
Peptidase_M24 | PF00557.30 | 2.3e-50 | 48–276 | Metallopeptidase family M24 |
Functional interaction network (STRING v12, guilt-by-association)
| Partner | Product | Score | No text-mining | Channels (≥400) |
|---|---|---|---|---|
Rv0701 rplC |
50S ribosomal protein L3 | 964 | 963 | coexpression:700 experimental:808 |
Rv0714 rplN |
50S ribosomal protein L14 | 956 | 957 | coexpression:732 experimental:801 |
Rv0719 rplF |
50S ribosomal protein L6 | 957 | 956 | coexpression:737 experimental:793 |
Rv0720 rplR |
50S ribosomal protein L18 | 956 | 954 | coexpression:731 experimental:816 |
Rv0704 rplB |
50S ribosomal protein L2 | 956 | 954 | coexpression:709 experimental:800 |
Rv0708 rplP |
50S ribosomal protein L16 | 955 | 954 | coexpression:731 experimental:794 |
Rv0709 rpmC |
50S ribosomal protein L29 | 955 | 953 | coexpression:730 experimental:813 |
Rv0702 rplD |
50S ribosomal protein L4 | 953 | 952 | coexpression:705 experimental:794 |
Rv0722 rpmD |
50S ribosomal protein L30 | 955 | 951 | coexpression:731 experimental:802 |
Rv0715 rplX |
50S ribosomal protein L24 | 951 | 951 | coexpression:727 experimental:807 |
Rv0716 rplE |
50S ribosomal protein L5 | 950 | 949 | coexpression:669 experimental:803 |
Rv0721 rpsE |
30S ribosomal protein S5 | 947 | 948 | coexpression:725 experimental:701 |
Rv0706 rplV |
50S ribosomal protein L22 | 948 | 945 | coexpression:717 experimental:793 |
Rv0703 rplW |
50S ribosomal protein L23 | 947 | 944 | coexpression:676 experimental:820 |
Rv3443c rplM |
50S ribosomal protein L13 | 943 | 940 | coexpression:656 experimental:800 |
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
- Annotation from H37Rv (no MTBC0 1:1 anchor; H37Rv protein used): methionine aminopeptidase
- Pfam (hmmscan --cut_ga): Peptidase_M24 PF00557.30 (E=2e-50)
- (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 YP_177911.1)
- Domains: Pfam-A via hmmscan --cut_ga — Peptidase_M24 (PF00557.30)
- 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
COG0024 - Curated reference: UniProt P9WK19 (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 — 139 functional partner(s)
- Primary literature: none located yet; annotation rests on the domain/homology sources above.
Ancestral MTBC0 protein sequence
>H37Rv|Rv2861c|mapB MPSRTALSPGVLSPTRPVPNWIARPEYVGKPAAQEGSEPWVQTPEVIEKMRVAGRIAAGALAEAGKAVAPGVTTDELDRIAHEYLVDNGAYPSTLGYKGFPKSCCTSLNEVICHGIPDSTVITDGDIVNIDVTAYIGGVHGDTNATFPAGDVADEHRLLVDRTREATMRAINTVKPGRALSVIGRVIESYANRFGYNVVRDFTGHGIGTTFHNGLVVLHYDQPAVETIMQPGMTFTIEPMINLGALDYEIWDDGWTVVTKDRKWTAQFEHTLLVTDTGVEILTCL