Rv3312A Resolved · high auto-curated

H37Rv Rv3312A · MTBC0 - · 103 aa · 3700705–3701016 (-) · RefSeq YP_177957.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)pilin
MTBC0 PGAP re-annotation
Revised (this work)Pilin. Pfam: Pilin_Mycobact (PF26380.2).

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 P9WI87 SwissProt · reviewed · Evidence at protein level
UniProt namePilin
Curated functionStructural subunit of M.tuberculosis pili (MTP), which are thin (2- to 3-nm wide), flexible, coiled-coil, aggregative fibers. Has a strong affinity for laminin but lacks significant binding affinity for fibronectin or type IV collagen. Mediates adhesion to the extracellular matrix, an event that would facilitate direct interaction with the host epithelium during infection in the lung or other tissues.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
Preferred namemtp
eggNOG descriptionStructural subunit of M.tuberculosis pili (MTP), which are thin
Orthologous group2B1R9
Gene Ontology (15) GO:0005575, GO:0005623, GO:0008150, GO:0009289, GO:0009297, GO:0009987, GO:0016043, GO:0022607, GO:0030030, GO:0030031, GO:0042995, GO:0043711 +3 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 0.326 · purifying
Polymorphic sites (≥ 0.1% of strains) 1 synonymous, 1 missense, 0 nonsense, 1 frameshift
Disruption 1 distinct premature-stop/frameshift site(s); most common in 0.14% of strains (207) · 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)

PfamAccessioni-EvalueResiduesDescription
Pilin_MycobactPF26380.2 1.8e-1630–62 Mycobacterial Pilin Family

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

Closest characterised functional partner: add (adenosine deaminase), medium confidence from genomic context alone (score 629 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv3313c add adenosine deaminase 628 629 ctx neighborhood:624
Rv3314c deoA thymidine phosphorylase 707 625 ctx neighborhood:624
Rv3315c cdd cytidine deaminase 643 601 ctx neighborhood:597
Rv3312c hyp hypothetical protein 549 394
Rv0309 hyp hypothetical protein 556 58 textmining:549
Rv1824 hyp hypothetical protein 805 54 textmining:803
Rv3717 hyp hypothetical protein 443 52 textmining:437
Rv3441c mrsA phosphoglucosamine mutase 442 47 textmining:439
Rv0475 hbhA heparin binding hemagglutinin HbhA 653 46 textmining:652
Rv2296 dhmA1 haloalkane dehalogenase 575 46 textmining:573
Rv2338c moeW molybdopterin biosynthesis protein MoeW 548 46 textmining:546
Rv0021c hyp hypothetical protein 630 41 textmining:630
Rv3503c fdxD ferredoxin FdxD 510 41 textmining:510

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): pilin
  • Pfam (hmmscan --cut_ga): Pilin_Mycobact PF26380.2 (E=2e-16)
  • (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_177957.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Pilin_Mycobact (PF26380.2)
  • 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 2B1R9
  • Curated reference: UniProt P9WI87 (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 — 13 functional partner(s); context anchor add
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>H37Rv|Rv3312A|
MYRFACRTLMLAACILATGVAGLGVGAQSAAQTAPVPDYYWCPGQPFDPAWGPNWDPYTCHDDFHRDSDGPDHSRDYPGPILEGPVLDDPGAAPPPPAAGGGA