Rv0247c Family assigned · medium auto-curated

H37Rv Rv0247c · MTBC0 mtbc0_000263 · 248 aa · 298498–299244 MTBC0 (-) · RefSeq NP_214761.1

Genomic neighbourhood (genome browser)

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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)succinate dehydrogenase iron-sulfur subunit
MTBC0 PGAP re-annotationsuccinate dehydrogenase/fumarate reductase iron-sulfur subunit
Revised (this work)Succinate dehydrogenase/fumarate reductase iron-sulfur subunit. Pfam: Fer2_3 (PF13085.12), Fer2 (PF00111.33), Fer4_8 (PF13183.12).
Functional category (TubercuList)intermediary metabolism and respiration

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) 2 publications

2 TB publications mention this gene. 2 publication(s) discuss this gene (1 in a M. tuberculosis context, 1 in other mycobacteria — M. smegmatis (1)).

PublicationDate
Role of intragenic binding of cAMP responsive protein (CRP) in regulation of the succinate dehydrogenase genes Rv0249c-Rv0247c in TB complex mycobacteria. doi:10.1093/nar/gkv420 2015
Novel regulatory roles of cAMP receptor proteins in fast-growing environmental mycobacteria. doi:10.1099/mic.0.000015 2015

This layer CITES the literature and adds context; it does not change the verdict or the function stated elsewhere in this fiche. This distinguishes a gene that is dark because nobody has looked from one that is dark despite having been studied. Source: PubMed (whole): H37Rv locus tag + GENE NAME + ortholog identifiers (Mb…, MMAR_…, MSMEG_…, ML…, MAB_…), under a mycobacterial context filter; hits verified against the abstract text. Species-context counts distinguish M. tuberculosis literature from literature on other mycobacteria. phase76/phase77, 2026-07-13.

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

NeighbourRv0246 (Rv0246, + 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.

CRISPRi vulnerability

Vulnerability index 1.08 (95% CI -0.21 to 3.26). 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, pebble.rockefeller.edu).

Legacy record & comparison (Mycobrowser)

Mycobrowser functionInvolved in interconversion of fumarate and succinate (aerobic respiration) [catalytic activity: succinate + acceptor = fumarate + reduced acceptor].
Mycobrowser EC 1.3.99.1 · superseded EC numbering; the atlas uses the current class (1.3.5.1, 1.3.5.4)

The legacy Mycobrowser record is shown for verification. Mycobrowser is no longer maintained; its EC numbers predate recent nomenclature revisions, so a class change usually reflects re-numbering, not a conflict.

Orthologues (reciprocal best hits across mycobacteria)

M. bovis Mb0253c · 100.0% identity
M. marinum MMAR_0510 · 93.1% identity
M. smegmatis MSMEG_0417 · 84.2% identity
M. orygis RJtmp_000263 · 100.0% identity
M. abscessus MAB_4423 · 81.0% 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 O53669 TrEMBL · unreviewed · Evidence at protein level
UniProt nameProbable succinate dehydrogenase [iron-sulfur subunit]

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category C Energy production and conversion
Preferred namesdhB_1
eggNOG descriptionfumarate reductase
Orthologous groupCOG0479
EC number EC 1.3.5.1, EC 1.3.5.4
KEGG orthology K00240
KEGG pathways map00020, map00190, map00650, map00720, map01100, map01110, map01120, map01130, map01200
KEGG modules M00009, M00011, M00149, M00173, M00374, M00376

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 0.144 · strong purifying
Polymorphic sites (≥ 0.1% of strains) 2 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) Bacteria

Genus-wide presence (~53 non-MTBC Mycobacterium) present in 53/53 (100%) · mean identity 88.2% · 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 5/13 non-Mycobacterium reference genomes (down to Bacteria) · mean identity 69.7%
detected down to outside the phylum (Proteobacteria/Firmicutes controls) — a universally conserved, ancient bacterial 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)

DeJesus 2017 callNE · non-essential
What the call meansnon-essential
TA sites (Himar1) 13 in the ORF — 0 in the essential state, 0 growth-defect, 13 non-essential, 0 growth-advantage. Saturation 0.846, mean read count 35.6363636364. A region of the protein devoid of TA sites is invisible to this assay: nothing can be inferred about it, in either direction.

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.

Mutant phenotypes (conditional Tn-seq, MtbTnDB) in-vivo phenotype

Conditionlog2FCqEffect
fitness in mouse infection, day 10 (in vivo) -4.400.0 required
altered fitness under Isoniazid (drug exposure) +4.050.0032 disruption advantageous
altered fitness under 6 weeks hypoxia (stress) -3.470.0 required

Conditional fitness of transposon-disruption mutants across 3 significant condition(s) (|log2FC|≥1, q≤0.05), from the standardized MtbTnDB compendium. A negative log2FC means the mutant is depleted — the gene contributes to fitness in that condition. An in-vivo defect for a "hypothetical" is strong evidence it matters for infection, even without a known molecular function. Disruption (Tn insertion), not a clean deletion; genetic-interaction screens excluded.

Proteomics (mass spectrometry) detected

MS detectiondetected in 16 of 16 independent MS datasets
Integrated abundance537.0 ppm · rank 382/3519 (89.2th 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. Reproducible detection across several independent datasets (PaxDb) makes the existence claim robust; the integrated abundance places the protein in the proteome's dynamic range.

Physico-chemical properties (computed, ProtParam)

Length248 aa
Molecular weight28.6 kDa
Theoretical pI5.92
GRAVY-0.455 (hydrophilic)
Aliphatic index72.7
Aromaticity0.073
Instability index54.8 (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
Fer2_3PF13085.12 1.6e-248–105 2Fe-2S iron-sulfur cluster binding domain
Fer2PF00111.33 3.0e-0421–69 2Fe-2S iron-sulfur cluster binding domain
Fer4_8PF13183.12 1.1e-08141–216 4Fe-4S dicluster domain

Structural search (AlphaFold DB model, Foldseek vs PDB — genome-wide) pLDDT 95.3

PDB hitprobTM-scoreE-valueDescription
7d6x-assembly1_B 1.00 0.99 3.2e-38 sig 7d6x-assembly1_B Mycobacterium smegmatis Sdh1 complex in the apo form
2bs2-assembly1_B 1.00 0.87 1.1e-17 sig 2bs2-assembly1_B QUINOL:FUMARATE REDUCTASE FROM WOLINELLA SUCCINOGENES
2wp9-assembly3_J 1.00 0.88 3.0e-16 sig 2wp9-assembly3_J Crystal structure of the E. coli succinate:quinone oxidoreductase (SQR) SdhB His207Thr mutant
1kf6-assembly1_B 1.00 0.87 1.4e-16 sig 1kf6-assembly1_B E. coli Quinol-Fumarate Reductase with Bound Inhibitor HQNO
2fbw-assembly2_O 1.00 0.86 1.2e-15 sig 2fbw-assembly2_O Avian respiratory complex II with carboxin bound

Foldseek search of the AlphaFold DB model (mean pLDDT 95.3, gated at 70) against the PDB — a genome-wide extension of the ESMFold dark-gene search that also covers proteins beyond the single-sequence length limit. Confident structural neighbours (E < 0.01) shown.

Genomic context (neighbours & predicted operon) operon of 3

Upstream (5' on genome)Rv0246 (+ strand, -4 bp gap)
Downstream (3' on genome)Rv0248c (- strand, 0 bp gap)
Predicted operon Rv0247c · Rv0248c · Rv0249c

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).

Transcriptional regulation (signed TRN: ChIP-seq + TFOE)

Regulated by (1 TF) mmpR5 (activates)

Regulatory edges from the ISB signed transcriptional regulatory network (TF ChIP-seq binding, Minch 2015 + TF-overexpression response, Rustad 2014). An edge is regulatory evidence (binding and/or expression change), not necessarily direct. For a "hypothetical", membership in a known regulon (e.g. DosR dormancy, PhoP virulence) is a strong physiological-context lead.

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

Explore full network →

Node colour = verdict, dashed = hypothetical; 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: Rv0249c (succinate dehydrogenase membrane anchor subunit), high confidence from genomic context alone (score 1000 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv0249c exp succinate dehydrogenase membrane anchor subunit 999 1000 ctx neighborhood:839 cooccurence:774 experimental:997 textmining:870
Rv0248c exp succinate dehydrogenase flavoprotein subunit 999 1000 ctx neighborhood:881 cooccurence:774 coexpression:882 experimental:997 database:956 textmining:852
Rv3316 sdhC exp succinate dehydrogenase cytochrome B-556 subunit 999 998 coexpression:696 experimental:788 database:962 textmining:861
Rv3317 sdhD exp succinate dehydrogenase hydrophobic membrane anchor subunit 998 993 coexpression:670 experimental:784 database:900 textmining:822
Rv1552 frdA exp fumarate reductase flavoprotein subunit 995 991 coexpression:484 experimental:454 database:956 textmining:483
Rv3318 sdhA exp succinate dehydrogenase flavoprotein subunit 995 990 coexpression:491 experimental:454 database:956 textmining:569
Rv0952 sucD exp succinyl-CoA ligase subunit alpha 979 976 coexpression:668 database:900
Rv0951 sucC exp succinyl-CoA ligase subunit beta 981 975 coexpression:656 database:900
Rv1554 frdC exp fumarate reductase membrane anchor subunit 983 974 coexpression:452 experimental:549 database:900
Rv1555 frdD exp fumarate reductase membrane anchor subunit 981 972 coexpression:417 experimental:549 database:900
Rv1098c fum exp fumarate hydratase 956 951 coexpression:445 database:900
Rv1248c kgd multifunctional 2-oxoglutarate dehydrogenase E1 component /2-oxoglutarate dehydrogenase dihydrolipoyllysine-residue succinyltransferase 967 950 coexpression:931
Rv1553 frdB exp fumarate reductase iron-sulfur subunit 924 915 database:900
Rv0234c gabD1 exp succinate-semialdehyde dehydrogenase 915 912 database:900
Rv1731 gabD2 exp succinate-semialdehyde dehydrogenase 915 912 database:900

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 exp badge marks an experimentally-supported partner (measured interaction, experimental/database channel ≥400) as opposed to a purely predicted one — but note that the M. tuberculosis experimental interactome is dominated by a noisy bacterial-two-hybrid screen, so a strong measured link that contradicts the operon/localisation context is likely a false positive. 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: succinate dehydrogenase iron-sulfur subunit
  • MTBC0 PGAP product: succinate dehydrogenase/fumarate reductase iron-sulfur subunit
  • Pfam (hmmscan --cut_ga): Fer2_3 PF13085.12 (E=2e-24), Fer2 PF00111.33 (E=3e-04), Fer4_8 PF13183.12 (E=1e-08)
  • (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_214761.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Fer2_3 (PF13085.12), Fer2 (PF00111.33), Fer4_8 (PF13183.12)
  • 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 COG0479
  • Curated reference: UniProt O53669 (TrEMBL, unreviewed; 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)
  • 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 95.3)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 99 functional partner(s); context anchor Rv0249c
  • 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)
  • Transcriptional regulation: ISB signed TRN — TF ChIP-seq (Minch et al. 2015, doi:10.1038/ncomms6829) + TF overexpression (Rustad et al. 2014, doi:10.1186/gb-2014-15-11-502)
  • Mutant phenotypes: standardized Tn-seq compendium MtbTnDB (Jinich et al. 2025, doi:10.1111/mmi.15370), aggregating many primary Tn-seq studies across conditions
  • Physico-chemical properties: ExPASy ProtParam method via Biopython (Gasteiger et al. 2005), computed from the MTBC0 sequence
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_000263|Rv0247c|
MTYSASMRVWRGDESCGELREFTVEVNEGEVVLDVILRLQQTQTPDLAVRWNCKAGKCGSCSAEINGKPRLMCMTRMSTFDEDEIVTVTPMRTFPVIRDLVTDVSFNYQKAREIPSFAPPKELQPSEYRMAQVDVARSQEFRKCIECFLCQNVCHVVRDHEENKDAFAGPRFLMRIAELEMHPLDTRDRRSQAQEEHGLGYCNITKCCTEVCPENIKITDNALIPMKERVADRKYDPVVWLGSKLFRR