Rv3440c Family assigned · low auto-curated · to review

H37Rv Rv3440c · MTBC0 mtbc0_003659 · 103 aa · 3885551–3885862 (-) · RefSeq NP_217957.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)hypothetical protein
MTBC0 PGAP re-annotationhypothetical protein
Revised (this work)No Pfam domain above threshold; Foldseek indicates a fold similar to 5los-assembly1_A Piriformospora indica PIIN_05872 (prob 0.96, TM 0.86). Structure-based, putative.

Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed (flagged for human review).

Curated reference (UniProt)

UniProt O06257 TrEMBL · unreviewed · Predicted
UniProt nameUncharacterized protein

UniProt still lists this protein as Uncharacterized protein; the revised annotation above is ahead of the current UniProt record.

Functional vocabulary (eggNOG-mapper, orthology transfer)

Orthologous group2BI3A

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 0.0 · strong purifying
Polymorphic sites (≥ 0.1% of strains) 1 synonymous, 0 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)

No Pfam-A domain above the gathering threshold (or not yet scanned).

Structural neighbours (Foldseek on the ESMFold model, exploratory)

ESMFold model confidence: mean pLDDT 67.4 (low). Low-confidence model: the fold may be unreliable, so treat these structural hits with caution.

Best matches against the PDB, ranked by Foldseek homology probability. A high probability / TM-score suggests a shared fold; unless flagged sig (E < 0.01) these are fold hypotheses, not assignments.

TargetProbTME-valueDescription
5los-assembly1_A 0.96 0.86 1.3e+00 5los-assembly1_A Piriformospora indica PIIN_05872
6tz5-assembly1_AA 0.63 0.73 2.8e+00 6tz5-assembly1_AA CryoEM reconstruction of membrane-bound ESCRT-III filament composed of CHMP1B+IST1 (left-handed)
7zch-assembly1_B 0.35 0.66 5.0e+00 7zch-assembly1_B CHMP2A-CHMP3 heterodimer (410 Angstrom diameter)
8v2q-assembly1_A-1 0.35 0.72 5.7e+00 8v2q-assembly1_A-1 CHMP1B/IST1 ssRNA bound copolymer
6zw6-assembly1_A 0.08 0.44 9.8e+00 6zw6-assembly1_A C16 symmetry: Bacterial Vipp1 and PspA are members of the ancient ESCRT-III membrane-remodeling superfamily.
6zw5-assembly1_A 0.07 0.44 9.2e+00 6zw5-assembly1_A C15 symmetry: Bacterial Vipp1 and PspA are members of the ancient ESCRT-III membrane-remodeling superfamily.

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

Closest characterised functional partner: mrsA (phosphoglucosamine mutase), high confidence from genomic context alone (score 826 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.

PartnerProductScoreNo text-miningChannels (≥400)
Rv3439c hyp hypothetical protein 932 932 ctx neighborhood:882 coexpression:449
Rv3441c mrsA phosphoglucosamine mutase 826 826 ctx neighborhood:816
Rv3442c rpsI 30S ribosomal protein S9 725 726 ctx neighborhood:722
Rv3443c rplM 50S ribosomal protein L13 526 526 ctx neighborhood:523

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: hypothetical protein
  • MTBC0 PGAP product: hypothetical protein
  • Foldseek best: 5los-assembly1_A Piriformospora indica PIIN_05872 (prob 0.96, E=1e+00, TM=0.86)
  • (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_217957.1)
  • Domains: Pfam-A via hmmscan --cut_ga — none above threshold
  • 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 2BI3A
  • Curated reference: UniProt O06257 (TrEMBL, unreviewed; Predicted)
  • Intra-MTBC selection: pN/pS and disruption from SPDI variants of 145 209 MTBC strains (this work, local collection vs H37Rv NC_000962.3)
  • Model confidence: ESMFold per-residue pLDDT (mean 67.4, low)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 4 functional partner(s); context anchor mrsA
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003659|Rv3440c|
MRPDSVNSAGIDIAAVYAVADRFSAAAELIDDAIGNHLTRLAFGGACAGRGHASRGDALRCRLDRLAGELSVWSRAAVQIAFALRAGANRYAEADLCAAARIG