apa Family assigned · medium auto-curated

H37Rv Rv1860 · MTBC0 - · 325 aa · 2107736–2108713 (+) · RefSeq YP_177849.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)hypothetical protein
MTBC0 PGAP re-annotation
Revised (this work)Contains FAP (PF07174.18) domain(s); putative function inferred from the domain architecture.

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 P9WIR7 SwissProt · reviewed · Evidence at protein level
UniProt nameAlanine and proline-rich secreted protein Apa
Curated functionA potent antigen in animals immunized with live bacteria, it induces a strong delayed-type hypersensitivity (DTH) in immunized animals. Elicits a mostly Th1 type of T-cell response in healthy humans; induces IFN-gamma production from CD4(+) and CD8(+) cells. Functions as an adhesin, binds to mouse macrophages via mannose residues. Might interact via host CD209.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
Preferred nameapa
eggNOG descriptionPFAM Fibronectin-attachment
Orthologous group2FEYE
Gene Ontology (49) GO:0002682, GO:0002684, GO:0005575, GO:0005576, GO:0006950, GO:0007154, GO:0008150, GO:0009267, GO:0009605, GO:0009607, GO:0009987, GO:0009991 +37 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 0.369 · 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)

PfamAccessioni-EvalueResiduesDescription
FAPPF07174.18 9.8e-88112–296 Fibronectin-attachment protein (FAP) domain

Functional interaction network (STRING v12, guilt-by-association)

Closest characterised functional partner: modC (molybdenum ABC transporter ATP-binding protein ModC), high confidence from genomic context alone (score 797 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.

PartnerProductScoreNo text-miningChannels (≥400)
Rv1859 modC molybdenum ABC transporter ATP-binding protein ModC 801 797 ctx neighborhood:796
Rv1857 modA molybdate ABC transporter substrate-binding lipoprotein ModA 682 652 ctx neighborhood:652
Rv1858 modB molybdenum ABC transporter permease ModB 628 620 ctx neighborhood:620
Rv1861 transmembrane protein 550 551 ctx neighborhood:544
Rv1862 adhA alcohol dehydrogenase A 544 544 ctx neighborhood:544
Rv1856c oxidoreductase 424 424 ctx neighborhood:422
Rv0934 pstS1 phosphate ABC transporter substrate-binding lipoprotein PstS 539 89 textmining:515
Rv3763 lpqH lipoprotein LpqH 681 64 textmining:674
Rv1886c fbpB diacylglycerol acyltransferase/mycolyltransferase Ag85B 632 55 textmining:627
Rv0309 hyp hypothetical protein 518 55 textmining:511
Rv1096 glycosyl hydrolase 432 55 textmining:424
Rv0350 dnaK chaperone protein DnaK 519 54 textmining:513
Rv3418c groES chaperonin GroES 657 52 textmining:654
Rv0440 groEL2 molecular chaperone GroEL 441 51 textmining:436
Rv1926c mpt63 immunogenic protein Mpt63 804 50 textmining:803

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): hypothetical protein
  • Pfam (hmmscan --cut_ga): FAP PF07174.18 (E=1e-87)
  • (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_177849.1)
  • Domains: Pfam-A via hmmscan --cut_ga — FAP (PF07174.18)
  • 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 2FEYE
  • Curated reference: UniProt P9WIR7 (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 — 27 functional partner(s); context anchor modC
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>H37Rv|Rv1860|apa
MHQVDPNLTRRKGRLAALAIAAMASASLVTVAVPATANADPEPAPPVPTTAASPPSTAAAPPAPATPVAPPPPAAANTPNAQPGDPNAAPPPADPNAPPPPVIAPNAPQPVRIDNPVGGFSFALPAGWVESDAAHFDYGSALLSKTTGDPPFPGQPPPVANDTRIVLGRLDQKLYASAEATDSKAAARLGSDMGEFYMPYPGTRINQETVSLDANGVSGSASYYEVKFSDPSKPNGQIWTGVIGSPAANAPDAGPPQRWFVVWLGTANNPVDKGAAKALAESIRPLVAPPPAPAPAPAEPAPAPAPAGEVAPTPTTPTPQRTLPA