sepH Resolved · medium auto-curated

H37Rv Rv0883c · MTBC0 mtbc0_000938 · 253 aa · 983720–984481 MTBC0 (-) · RefSeq NP_215398.1

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This gene (outlined) in its genomic context; arrows are neighbouring genes coloured by verdict. Click any gene to navigate. Pan and zoom in the full browser.

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)hypothetical protein
MTBC0 PGAP re-annotationseptation protein SepH
Revised (this work)Septation protein SepH.
Functional category (TubercuList)conserved hypotheticals

Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.

In the literature (TB corpus sweep) 1 publication

Found under: H37Rv (1).

1 TB publication mentions this gene. 1 publication(s) mention this gene (title/abstract), verified against the text. The atlas states the function; these are the primary sources that discuss it.

PublicationDate
Isolation of conditional expression mutants in Mycobacterium tuberculosis by transposon mutagenesis. doi:10.1016/j.tube.2011.07.004 2011
2 records returned by the alias sweep (a separate sweep from the 1 above; both are shown, neither is exhaustive)

Searched as: Rv0883c, sepH, Mb0907c, ML2137, MMAR_4649, MSMEG_5685, MAB_0883c — each in conjunction with a mycobacterial context term. Swept 2026-09-07.

PublicationJournalYear
A conserved cell division protein directly regulates FtsZ dynamics in filamentous and unicellular actinobacteria. doi:10.7554/eLife.63387 Elife 2021
Isolation of conditional expression mutants in Mycobacterium tuberculosis by transposon mutagenesis. doi:10.1016/j.tube.2011.07.004 Tuberculosis (Edinb) 2011

Title+abstract index only: a paper that names this gene solely in its body text, a figure legend or a supplement is invisible here. That is why this list sits beside the curated layer rather than replacing it - Rv0007's characterisation, found by a full-text sweep, returns zero in this one. Absence from this list is not absence from the literature. Source: PubMed E-utilities sweep (esearch + esummary), every alias of the gene searched in conjunction with a mycobacterial context term; ambiguous common-word aliases excluded. phase198, 2026-09-06.

This layer CITES the literature, it does not change the verdict or the function. A gene may be heavily studied (as an antigen, a resistance determinant, a drug target) while its molecular function is settled elsewhere in the fiche. This distinguishes a gene that is dark because nobody has looked from one that is dark despite having been studied. Source: PubMed (whole), MULTI-ALIAS sweep: H37Rv locus tag AND every ortholog identifier (M. bovis Mb…, M. marinum MMAR_…, M. smegmatis MSMEG_…, M. leprae ML…, M. abscessus MAB_…), each hit VERIFIED against the abstract text (word-boundary regex). phase73/phase75, 2026-07-13.

Intrinsic disorder (sequence + structure) partially disordered

Predicted disorder17% of residues (metapredict) · mean AlphaFold pLDDT 82.5
Disordered regions1 IDR(s), longest 43 aa [210-253]

carries a substantial disordered region (43/253 residues); disorder is a property, not a function

A property (biophysics), not a function. No LLPS/condensate claim is made from disorder alone. Verdict unchanged. Source: metapredict v3 (Emenecker/Holehouse) per-residue disorder + AlphaFold mean pLDDT (annotation_mtbc P16.13).

Genomic-neighbour overlap (structural caveat) antiparallel · 1 % of gene

NeighbourRv0882 (Rv0882, + strand)
Overlap4 bp, 1 % of this gene's length

antiparallel overlap: this gene may inherit essentiality/conservation signal from its neighbour through shared TA sites or promoter constraint, without any protein of its own being produced (cf. Rv2438A/nadE) Signals attributed to this gene (Tn-seq essentiality via shared TA sites, conservation via promoter constraint) should be cross-checked against the neighbour before being read as its own. P20.1, derived from GFF3 gene coordinates, 2026-08-03.

Conditional expression context (iModulons)

Member of 1 independently-modulated gene set(s): Rv1828/SigH (Rv1828 or sigH).

iModulon membership (independently-modulated gene sets from a 647-sample RNA-seq compendium): the conditional co-expression context. Co-expression is a regulatory context, NOT a molecular function. Source: iModulonDB / modulome_mtb (Yoo 2022).

CRISPRi vulnerability

Vulnerability index -9.89 (95% CI -10.83 to -8.92). A more negative index = more vulnerable to knockdown (better drug-target quality); indicative threshold VI ≤ -6 = highly vulnerable.

Quantitative CRISPRi knockdown, graded (finer than binary Tn-seq essentiality). Source: CRISPRi vulnerability index (Bosch 2021, supplementary Table S2 'mmc3.xlsx', bulk import via Europe PMC -- supersedes the per-gene pebble.rockefeller.edu scrape of phase46_crispri_vulnerability.py).

Legacy record & comparison (Mycobrowser) ahead of Mycobrowser

Mycobrowser functionFunction unknown

Mycobrowser classes this locus among conserved hypotheticals; the atlas now assigns a functional handle (requalified function). Mycobrowser is no longer maintained, so its EC numbers predate recent nomenclature revisions (e.g. the 2018 EC 7 "translocase" class) — most EC differences are re-numberings of the same enzyme, not conflicts.

Orthologues (reciprocal best hits across mycobacteria)

M. bovis Mb0907c · 100.0% identity
M. leprae ML2137 · 79.4% identity
M. marinum MMAR_4649 · 75.7% identity
M. smegmatis MSMEG_5685 · 64.1% identity
M. orygis RJtmp_000933 · 100.0% identity
M. abscessus MAB_0883c · 55.8% identity

Reciprocal-best-hit orthologues (DIAMOND) against the Mycobrowser reference proteomes. A missing species is informative: e.g. a gene absent from M. leprae was likely lost in its reductive genome evolution. Locus tags link to Mycobrowser.

Curated reference (UniProt)

UniProt P9WKQ7 SwissProt · reviewed · Evidence at protein level
UniProt nameUncharacterized protein Rv0883c

As checked on 2026-09-23, UniProt listed this protein as Uncharacterized protein Rv0883c; the revised annotation above goes beyond that record. UniProt may have been recurated since: check the live entry.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
eggNOG descriptionProtein of unknown function (DUF3071)
Orthologous group28PUQ
Gene Ontology (2) GO:0008150, GO:0040007

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, 142 601 strains, snapshot of 2026-09-29)

pN/pS 0.357 · quasi-invariant (2 sites), pN/pS underpowered
Polymorphic sites (≥ 0.1% of strains) 1 synonymous, 1 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.

Outgroup conservation (beyond the MTBC) Actinomycetia

M. canettii dN/dS (deep-divergence selection) 0.717 (low power) · 3 consensus substitution(s)
low power (3 canettii-consensus substitution(s)); present in M. canettii but dN/dS not reliable
Limitation: dN/dS mixes fixed canettii-H37Rv divergence with intra-canettii polymorphism, and is not polarised (the per-gene repolarisation is not viable: 79 % of the consensus SPDI lie outside the polarised table).
Genus-wide presence (~53 non-MTBC Mycobacterium) present in 53/53 (100%) · mean identity 73.8% · 4/4 closest MTBAP relatives
conserved across the genus (present in 53/53 non-MTBC Mycobacterium genomes, incl. distant relatives) — an ancient core gene predating the genus radiation
Phylostratum (deepest detected homolog) MTBC-specific → Mycobacterium → Mycobacteriaceae → Corynebacteriales → Actinomycetia → Bacteria
detected in 9/13 non-Mycobacterium reference genomes (down to Actinomycetia) · mean identity 44.7%
detected across the class Actinomycetia (beyond Corynebacteriales) but not outside the phylum — an Actinobacteria-level ancient gene

Two orthogonal outgroup signals. M. canettii (the immediate outgroup) gives a deep-divergence dN/dS (a low value confirms a constrained, real gene; shown as confident only at ≥8 substitutions, else flagged low-power). Genus-wide presence/absence (tblastn vs assembled non-MTBC genomes) places the gene on the ancient-core ↔ MTBC-specific axis: a gene absent even from the closest MTBAP relatives is a candidate MTBC-specific innovation (possible host-adaptation factor, to confirm by synteny). The phylostratum extends that axis outside the genus (tblastn vs 13 reference genomes spanning Mycobacteriaceae → Corynebacteriales → Actinomycetia → outside the phylum): it is the deepest clade in which a homolog is still detected, i.e. a proxy for gene age. Read it with the null model in mind: a shallow (young) stratum can also reflect homology-detection failure for short or fast-evolving ORFs, so it is a descriptive axis, not a proof of novelty.

Essentiality (transposon mutagenesis) essential

DeJesus 2017 callES · essential
What the call meansessential: insertions absent across the whole ORF
TA sites (Himar1) 7 in the ORF — 5 in the essential state, 0 growth-defect, 2 non-essential, 0 growth-advantage. Saturation 0.286, mean read count 4. A region of the protein devoid of TA sites is invisible to this assay: nothing can be inferred about it, in either direction.
6 of these 7 sites are exclusively this ORF's; Measured, not hypothetical: 1 of this ORF's 7 TA sites lies inside Rv0882 (1 site), leaving 6 sites that are exclusively its own. A transposon insertion cannot be assigned to one reading frame rather than the other, so the essentiality call rests on those 6 exclusive sites.
CaveatRead with some caution: only 7 TA (Himar1) sites in the whole ORF (atlas median 13). The DeJesus 2017 call rests on fewer independent observations than for a longer gene. If this gene overlaps a neighbour (see Genomic-neighbour overlap section below), some of these 7 sites may fall inside the neighbour's ORF rather than its own, leaving even fewer truly informative sites than the raw count suggests. (P20.3)

Genome-wide Himar1 transposon essentiality in H37Rv (DeJesus 2017). An essential call (ES/ESD/GD) is strong, independent evidence that a "hypothetical" locus encodes a functional, selectively required gene — orthogonal to intra-species conservation.

Proteomics (mass spectrometry) detected

MS detectiondetected in 9 of 16 independent MS datasets
Integrated abundance5.92 ppm · rank 2882/3519 (18.1th percentile)

Detection by mass spectrometry is direct, experimental evidence that the protein product exists — orthogonal to sequence conservation and to Tn-seq essentiality, and especially decisive for a "hypothetical" locus. Read the dataset count as abundance, not as replication. Measured across this atlas (3,491 detected proteins), the number of datasets a protein appears in tracks its abundance almost monotonically: median 1.2 ppm at 1 dataset of 16, 27 ppm at 10, 392 ppm at 15, 1,325 ppm at 16 — three orders of magnitude. A high count therefore says the protein is abundant more than it says several independent experiments confirmed it. What the count does establish, at any value, is that the product exists.

Predicted localisation (DeepTMHMM + lipobox) no export signal, no TM helix

Predictionno signal peptide, no TM helix (DeepTMHMM class GLOB)
DeepTMHMM classGLOB

A verified absence of signals, which is not a compartment. No Sec/Tat signal peptide, no transmembrane helix and no lipobox were found on this sequence. The predictor reports topology and export signals; it does not measure where the protein ends up, so this page draws no cytoplasmic conclusion from it. In M. tuberculosis that reservation is not theoretical: the 12 Esx paralogues of this atlas — EsxA/ESAT-6 and EsxB/CFP-10 among them, the best-established secreted proteins of the species — carry this very call, because substrates of the type VII (ESX) secretion system leave no recognisable signal. « Secreted » and « no signal peptide » are true together here.

Transmembrane topology and signal peptide from DeepTMHMM (deep-learning reference predictor); lipoproteins from a (myco)bacterial lipobox motif. A sequence-based prediction of subcellular context.

Physico-chemical properties (computed, ProtParam)

Length253 aa
Molecular weight27.4 kDa
Theoretical pI6.09
GRAVY-0.295 (hydrophilic)
Aliphatic index90.8
Aromaticity0.043
Instability index46.6 (unstable)

Computed from the ancestral MTBC0 sequence with the ExPASy ProtParam method (Biopython). Descriptive biophysical context: a positive GRAVY flags a hydrophobic (often membrane) protein, a high instability index (>40) predicts a short in-vitro half-life, an extreme pI hints at compartment or binding partner.

Domains (Pfam, hmmscan --cut_ga)

PfamAccessioni-EvalueResiduesDescription
DUF3071PF11268.14 1.1e-621–171 Protein of unknown function (DUF3071)

3D structure (interactive — Mol*/pdbe-molstar)

No experimental structure is deposited for this gene: showing the AlphaFold DB predicted model (mean pLDDT 82.5, confident), coloured by per-residue confidence (dark blue = very high, orange/red = low — treat low-confidence regions as unreliable, especially termini and loops). Drag to rotate, scroll to zoom.

Genomic context (neighbours & predicted operon)

Upstream (5' on genome)Rv0882 (+ strand, -4 bp gap)
Downstream (3' on genome)serC (- strand, 156 bp gap)

Neighbours from the H37Rv annotation (- strand). The operon is predicted by co-directional intergenic distance (same strand, gaps ≤50 bp) — a transcription-unit hypothesis, not a mapped TSS. For a "hypothetical", co-transcription with a characterised operon is a concrete functional lead (complements the STRING neighborhood channel below).

Published operon evidence (two independent sources)

Roback 2007 (logistic regression: distance + expression correlation, 474 microarrays) no multi-gene operon predicted (singleton)
REMap 2016 (RNA-seq coverage continuity, CDC1551, tag MT0906) exponential phase: operon of 2, Rv0883c · Rv0884c (coverage 53.04)
stationary phase: operon of 2, Rv0883c · Rv0884c (coverage 31.41) — disagrees with the distance heuristic above

Two independent published operon maps, cited alongside the distance heuristic above: an association corroborating or contradicting the heuristic, never proof of shared function. REMap's RNA-seq coverage continuity is the most direct of the three signals; Roback's logistic regression and the intergenic-distance heuristic are statistical proxies.

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

Explore full network →

Node colour = verdict, dashed = still uncharacterised; edge colour = evidence (green experimental, orange genomic-context, grey co-expression), width ∝ score. Click a partner to open its page; "Explore full network" to walk the graph.

Closest characterised functional partner: serC (phosphoserine aminotransferase), high confidence (score 752, all STRING channels except text-mining; the partner is chosen on its genomic-context evidence).

Showing the 15 strongest of this gene's 73 partners at medium confidence (5 at high confidence). The table is an extract, not a neighbourhood: across the proteome the real median degree is 34 while the served median is 15, so no hub, degree distribution or centrality may be read on this table. None of the 73 partners rests on an interaction measured in M. tuberculosis itself.

PartnerProductScoreNo text-miningChannels (≥400)
Rv0884c serC phosphoserine aminotransferase 751 752 ctx neighborhood:749
Rv0885 hypothetical protein 678 678 ctx neighborhood:677
Rv0886 fprB ferredoxin/ferredoxin--NADP reductase 669 670 ctx neighborhood:670
Rv1002c pmt dolichyl-phosphate-mannose--protein mannosyltransferase 619 619 ctx cooccurence:617
Rv3212 hypothetical protein 577 577 ctx cooccurence:573
Rv2413c hypothetical protein 565 566 ctx cooccurence:563
Rv2256c dark hypothetical protein 557 557 ctx cooccurence:553
Rv3311 hypothetical protein 538 539 ctx cooccurence:528
Rv0475 hbhA heparin binding hemagglutinin HbhA 549 532 ctx cooccurence:529
Rv2772c transmembrane protein 528 529 ctx cooccurence:525
Rv2146c transmembrane protein 527 528 ctx cooccurence:511
Rv2680 dark hypothetical protein 526 526 ctx cooccurence:513
Rv1364c sigma factor regulatory protein 522 518 coexpression:503
Rv2219 transmembrane protein 576 512 ctx cooccurence:509
Rv2169c dark transmembrane protein 506 506 ctx cooccurence:503

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.

Where the experimental evidence comes from, and why it matters here. STRING's experimental channel fuses interactions measured in M. tuberculosis with interactions measured in another organism and transferred to this pair by orthology. The two are not equivalent for this atlas, whose standing rule is that better studied elsewhere is not a function established in M. tuberculosis. Measured on the served network: of the 38 229 partner pairs shown across the atlas, 13 483 partner rows carry a non-zero experimental channel, and only 106 pairs rest on an interaction measured in M. tuberculosis itself — 0.3 % of the network. Those 106 are long-established complexes (ESX-1/ESAT-6, RNA polymerase with CarD and RbpA, the Pup–Mpa proteasome, gyrase, Emb, GarA with PknB and PknG, the Rel modules); no still-uncharacterised gene is among them. The reason is not a gap in this atlas but in the literature: there is almost no experimental interactome of this bacterium, IntAct holding 134 curated protein pairs for a ~4 000-gene proteome. A exp (transferred) badge is therefore a lead, never a measurement, and an absence of badge is not evidence that the pair does not interact.

Evidence

  • Legacy H37Rv annotation: hypothetical protein
  • MTBC0 PGAP product: septation protein SepH
  • Pfam (hmmscan --cut_ga): DUF3071 PF11268.14 (E=1e-62)
  • (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_215398.1)
  • Domains: Pfam-A via hmmscan --cut_ga — DUF3071 (PF11268.14)
  • 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 28PUQ
  • Curated reference: UniProt P9WKQ7 (SwissProt, reviewed; Evidence at protein level)
  • Intra-MTBC selection: pN/pS and disruption from SPDI variants of 142 601 MTBC strains (this work, local collection vs H37Rv NC_000962.3)
  • Genome-wide structure: AlphaFold DB model (Jumper et al. 2021, doi:10.1038/s41586-021-03819-2; Varadi et al. 2024, doi:10.1093/nar/gkad1011) searched vs PDB with Foldseek (mean pLDDT 82.5)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 73 functional partner(s); context anchor serC
  • Essentiality: genome-wide transposon mutagenesis in H37Rv — DeJesus et al. 2017 (mBio, doi:10.1128/mBio.02133-16, CC BY)
  • Proteomics: integrated mass-spectrometry abundance from PaxDb 5.0 (Huang et al. 2023, doi:10.1016/j.mcpro.2023.100640), taxon 83332 — weighted average of 16 datasets, incl. Schubert et al. 2013 (doi:10.1016/j.chom.2013.04.008) and Albrethsen et al. 2013 (doi:10.1074/mcp.M112.018846)
  • Functional category: TubercuList scheme (Cole et al. 1998, doi:10.1038/31159), via Mycobrowser (Kapopoulou et al. 2011, doi:10.1016/j.tube.2010.09.006)
  • Orthologues: reciprocal best hits (DIAMOND, Buchfink et al. 2021, doi:10.1038/s41592-021-01101-x) against Mycobrowser release 5 reference proteomes
  • Genomic context / operon: H37Rv annotation; operon predicted by co-directional intergenic distance (Salgado et al. 2000, doi:10.1073/pnas.030539397)
  • Physico-chemical properties: ExPASy ProtParam method via Biopython (Gasteiger et al. 2005), computed from the MTBC0 sequence
  • Predicted localisation: DeepTMHMM (Hallgren et al. 2022, doi:10.1101/2022.04.08.487609) for transmembrane topology and signal peptide
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_000938|Rv0883c|sepH
MRELKVVGLDADGKNIICQGAIPSEQFKLPVDDRLRAALRDDSVQPEQAQLDIEVTNVLSPKEIQARIRAGASVEQVAAASGSDIARIRRFAHPVLLERSRAAELATAAHPVLADGPAVLTMQETVAAALVARGLNPDSLTWDAWRNEDSRWTVQLAWKAGRSDNLAHFRFTPGAHGGTATAIDDTAHELINPTFNRPLRPLAPVAHLDFDEPEPAQPTLTVPSAQPVSNRRGKPAIPAWEDVLLGVRSGGRR