Rv1717 Family assigned · medium auto-curated

H37Rv Rv1717 · MTBC0 mtbc0_001827 · 116 aa · 1956421–1956771 MTBC0 (+) · RefSeq NP_216233.1

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)hypothetical protein
MTBC0 PGAP re-annotationcupin domain-containing protein
Revised (this work)Cupin domain-containing protein. Pfam: Cupin_2 (PF07883.18).
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
Rv1717 Is a Cell Wall - Associated β-Galactosidase of Mycobacterium tuberculosis That Is Involved in Biofilm Dispersion. doi:10.3389/fmicb.2020.611122 2020

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.

Phenotype-driven functional lead (hypothesis) priority 5.0

disruption advantageous under acid stress in phosphate-citrate buffer.

Corroborating evidenceconserved / under constraint intra-MTBC; STRING-coupled to fadB3 (3-hydroxybutyryl-CoA dehydrogenase FadB); co-transcribed with fadB3; structural lead available

This locus is a "hypothetical" with a conditional Tn-seq phenotype. The statement above is a working hypothesis for its functional context, synthesised from the phenotype pattern and the corroborating layers on this page (conservation, STRING coupling, operon, regulon, localisation, structure) — a prioritised requalification candidate to validate, not an established function.

Genomic-neighbour overlap (structural caveat) co-directional · 0 % of gene

NeighbourRv1716 (Rv1716, + strand)
Overlap1 bp, 0 % of this gene's length

co-directional overlap: ordinary (e.g. shared stop/start codons in an operon), not the Rv2438A-type artefact P20.1, derived from GFF3 gene coordinates, 2026-08-03.

Conditional expression context (iModulons)

Member of 1 independently-modulated gene set(s): SG_8.

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 -2.09 (95% CI -6.62 to 2.38). 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) ahead of Mycobrowser

Mycobrowser functionFunction unknown

Mycobrowser classes this locus among conserved hypotheticals; the atlas now assigns a functional handle (curated function (UniProt), EC number). 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 Mb1745 · 100.0% identity
M. orygis RJtmp_001796 · 99.1% 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 O86372 SwissProt · reviewed · Evidence at protein level
UniProt nameBeta-D-galactosidase Rv1717
EC (curated) EC 3.2.1.23
Curated functionBeta-D-galactopyranosidase that specifically recognizes the beta-glycosidic bonds formed with beta-D-galactopyranose (beta-D-Gal) or N-acetylgalactosamine (beta-D-GalNAc). May target the galactoside linkages in the exopolysaccharide component of the mycobacterial extracellular polymeric substance (EPS) and help dispersal of Mtb bacteria from a deteriorating biofilm.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
eggNOG descriptionCupin domain
Orthologous groupCOG3837

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) pseudogene candidate

pN/pS 0.559 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 2 synonymous, 3 missense, 0 nonsense, 1 frameshift
Disruption 1 distinct premature-stop/frameshift site(s); most common in 10.21% of strains (14829) · 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.

Outgroup conservation (beyond the MTBC) Mycobacteriaceae

Genus-wide presence (~53 non-MTBC Mycobacterium) present in 11/53 (21%) · mean identity 71.9% · 2/4 closest MTBAP relatives
present in a subset of the genus (11/53 NTM; in 2 of the 4 closest MTBAP relatives) — partial/intermediate conservation
Phylostratum (deepest detected homolog) MTBC-specific Mycobacterium Mycobacteriaceae Corynebacteriales Actinomycetia Bacteria
detected in 1/13 non-Mycobacterium reference genomes (down to Mycobacteriaceae) · mean identity 39.3%
detected in the sister family Mycobacteriaceae (M. abscessus) but not in the broader Corynebacteriales — a Mycobacteriaceae-restricted gene (single-genome rung: interpret with care)

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) 4 in the ORF — 0 in the essential state, 0 growth-defect, 4 non-essential, 0 growth-advantage. Saturation 1.000, mean read count 92. A region of the protein devoid of TA sites is invisible to this assay: nothing can be inferred about it, in either direction.
CaveatStatistically thin call: only 4 TA (Himar1) sites in the whole ORF (atlas median 13; genes under 300 nt typically have very few). A DeJesus 2017 call built on so few independent observations is less robust than the same call on a longer gene, in either direction. Cross-check against the CRISPRi vulnerability index (independent of TA-site density) and, if this gene overlaps a neighbour (see Genomic-neighbour overlap section below), verify how many of its TA sites actually fall inside its own ORF. (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.

Mutant phenotypes (conditional Tn-seq, MtbTnDB)

Conditionlog2FCqEffect
altered fitness under acid stress in phosphate-citrate buffer (stress) +3.360.0 disruption advantageous

Conditional fitness of transposon-disruption mutants across 1 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) not detected

Not detected in the mass-spectrometry datasets integrated by PaxDb. This is not evidence of absence: low-abundance, condition-specific, or MS-refractory proteins (e.g. small, highly hydrophobic, or repetitive PE/PPE families with few tryptic peptides) are systematically under-sampled.

Physico-chemical properties (computed, ProtParam)

Length116 aa
Molecular weight12.7 kDa
Theoretical pI6.51
GRAVY-0.163 (hydrophilic)
Aliphatic index94.9
Aromaticity0.052
Instability index31.7 (stable)

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
Cupin_2PF07883.18 8.7e-0941–107 Cupin domain

Structural search (AlphaFold DB model, Foldseek vs PDB — genome-wide) pLDDT 96.7

PDB hitprobTM-scoreE-valueDescription
8awn-assembly1_A-2 1.00 0.87 9.6e-10 sig 8awn-assembly1_A-2 Crystal structure of a manganese-containing cupin (tm1459) from Thermotoga maritima, variant C106Q
8hjx-assembly1_B 1.00 0.86 1.5e-09 sig 8hjx-assembly1_B Crystal structure of a cupin protein (tm1459, H52A/H58E mutant) in copper (Cu) substituted form
8hjz-assembly1_B 1.00 0.86 2.4e-09 sig 8hjz-assembly1_B Crystal structure of a cupin protein (tm1459, H52A/H58Q mutant) in copper (Cu) substituted form
6l2f-assembly1_B 1.00 0.86 2.5e-09 sig 6l2f-assembly1_B Crystal structure of a cupin protein (tm1459, H54AH58A mutant) in copper (Cu) substituted form
8zyg-assembly1_B 1.00 0.86 3.5e-09 sig 8zyg-assembly1_B Crystal structure of a cupin protein (tm1459, I49C-4py/H52A/C106D mutant) in copper (Cu) substituted form

Foldseek search of the AlphaFold DB model (mean pLDDT 96.7, 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 4

Upstream (5' on genome)Rv1716 (+ strand, -1 bp gap)
Downstream (3' on genome)Rv1718 (+ strand, 52 bp gap)
Predicted operon Rv1714 · fadB3 · Rv1716 · Rv1717

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) Rv1719 (represses)

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: fadB3 (3-hydroxybutyryl-CoA dehydrogenase FadB), high confidence from genomic context alone (score 983 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.

PartnerProductScoreNo text-miningChannels (≥400)
Rv1716 hyp hypothetical protein 992 993 ctx neighborhood:882 cooccurence:615 coexpression:853
Rv1715 fadB3 3-hydroxybutyryl-CoA dehydrogenase FadB 982 983 ctx neighborhood:881 coexpression:815
Rv1714 oxidoreductase 976 976 ctx neighborhood:881 coexpression:767
Rv1718 hyp hypothetical protein 969 970 ctx neighborhood:717 coexpression:845
Rv1719 transcriptional regulator 784 785 ctx neighborhood:698
Rv3859c gltB glutamate synthase large subunit 544 544 ctx neighborhood:544
Rv0355c PPE8 PPE family protein PPE8 535 535 ctx cooccurence:534
Rv3347c PPE55 PPE family protein PPE55 527 527 ctx cooccurence:525
Rv3350c PPE56 PPE family protein PPE56 525 525 ctx cooccurence:524
Rv2209 integral membrane protein 514 514 ctx cooccurence:511
Rv1713 engA GTPase Der 513 513 ctx neighborhood:488
Rv3343c PPE54 PPE family protein PPE54 510 510 ctx cooccurence:503
Rv2490c PE_PGRS43 PE-PGRS family protein PE_PGRS43 510 510 ctx cooccurence:510
Rv1917c PPE34 PPE family protein PPE34 506 506 ctx cooccurence:502
Rv1712 cmk cytidylate kinase 495 495 ctx neighborhood:482

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: hypothetical protein
  • MTBC0 PGAP product: cupin domain-containing protein
  • Pfam (hmmscan --cut_ga): Cupin_2 PF07883.18 (E=9e-09)
  • (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_216233.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Cupin_2 (PF07883.18)
  • 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 COG3837
  • Curated reference: UniProt O86372 (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)
  • 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 96.7)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 42 functional partner(s); context anchor fadB3
  • Essentiality: genome-wide transposon mutagenesis in H37Rv — DeJesus et al. 2017 (mBio, doi:10.1128/mBio.02133-16, CC BY)
  • 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_001827|Rv1717|
MKLTRASQAPRYVAPAHHEVSTMRLQGREAGRTERFWVGLSVYRPGGTAEPAPTREETVYVVLDGELVVTVDGAETVLGWLDSVHLAKGELRSIHNRTDRQALLLVTVAHPVAEVA