Rv1045 Family assigned · medium auto-curated

H37Rv Rv1045 · MTBC0 mtbc0_001122 · 293 aa · 1175011–1175892 MTBC0 (+) · RefSeq NP_215561.1

Genomic neighbourhood (genome browser)

Open in full genome browser →

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-annotationnucleotidyl transferase AbiEii/AbiGii toxin family protein
Revised (this work)Nucleotidyl transferase AbiEii/AbiGii toxin family protein. Pfam: AbiEii (PF08843.18).
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) 3 publications

Found under: H37Rv (3).

3 TB publications mention this gene. 3 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
Identification of Genes Encoded Toxin-Antitoxin System in Mycobacterium Tuberculosis Strains from Clinical Sample. doi:10.2174/0118715265274164240117104534 2024
Characterization of a toxin-antitoxin system in Mycobacterium tuberculosis suggests neutralization by phosphorylation as the antitoxicity mechanism. doi:10.1038/s42003-020-0941-1 2020
Selective identification of new therapeutic targets of Mycobacterium tuberculosis by IVIAT approach. doi:10.1054/tube.2002.0337 2002

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.

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

NeighbourRv1044 (Rv1044, + strand)
Overlap4 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.

Post-translational modifications

1 reported modified residue(s), incl. 1 phosphosite(s): Phosphoserine @78.

Experimentally reported post-translational modification(s). A phosphosite indicates the protein is expressed and is a substrate of the M. tuberculosis Ser/Thr/Tyr kinase signalling network — a regulatory context, NOT a molecular function. Source: UniProt (Modified residue features; PTM sites curated from the M. tuberculosis literature).

CRISPRi vulnerability

Vulnerability index 1.01 (95% CI -0.48 to 3.25). 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).

Orthologues (reciprocal best hits across mycobacteria)

M. bovis Mb1074 · 99.3% 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 P96356 TrEMBL · unreviewed · Evidence at protein level
UniProt nameNucleotidyl transferase AbiEii/AbiGii toxin family protein

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
eggNOG descriptionNucleotidyl transferase AbiEii toxin, Type IV TA system
Orthologous group2DQGD

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 0.119 · strong purifying
Polymorphic sites (≥ 0.1% of strains) 3 synonymous, 1 missense, 0 nonsense, 2 frameshift
Disruption 2 distinct premature-stop/frameshift site(s); most common in 24.28% of strains (35261) · 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) Mycobacterium

Genus-wide presence (~53 non-MTBC Mycobacterium) present in 2/53 (4%) · mean identity 76.9% · 0/4 closest MTBAP relatives
absent from the closest MTBAP relatives and nearly all NTM (2/53) — a strong MTBC-restricted candidate (possible host-adaptation innovation, confirm by synteny)
Phylostratum (deepest detected homolog) MTBC-specific Mycobacterium Mycobacteriaceae Corynebacteriales Actinomycetia Bacteria

present across the genus Mycobacterium (NTM) but not detected in any non-Mycobacterium genome — a Mycobacterium-genus 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) 12 in the ORF — 0 in the essential state, 0 growth-defect, 12 non-essential, 0 growth-advantage. Saturation 1.000, mean read count 175.166666667. 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.

Proteomics (mass spectrometry) detected

MS detectiondetected in 9 of 16 independent MS datasets
Integrated abundance15.4 ppm · rank 2476/3519 (29.7th 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)

Length293 aa
Molecular weight32.0 kDa
Theoretical pI6.0
GRAVY-0.044 (hydrophilic)
Aliphatic index98.0
Aromaticity0.058
Instability index39.8 (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
AbiEiiPF08843.18 1.3e-1949–277 Nucleotidyl transferase AbiEii toxin, Type IV TA system

Experimental structures (Protein Data Bank) 12 solved

PDBMethodResolutionCoverage
6y5u X-ray diffraction 1.59 Å 100%
7c48 X-ray diffraction 1.6 Å 100%
8rr6 X-ray diffraction 1.78 Å 100%
6j7q X-ray diffraction 1.85 Å 100%
6j7o X-ray diffraction 1.9 Å 100%
6j7t X-ray diffraction 1.903 Å 100%
7c46 X-ray diffraction 1.93 Å 100%
8xhr X-ray diffraction 2.1 Å 100%

Experimentally solved structures mapped from the UniProt accession via PDBe/SIFTS (12 total; up to 8 shown, ranked by sequence coverage then resolution). An experimental structure is direct proof of the folded product and the strongest structural evidence — superseding the predicted ESMFold/AlphaFold models below for any covered region.

Structural search (AlphaFold DB model, Foldseek vs PDB — genome-wide) pLDDT 95.8

PDB hitprobTM-scoreE-valueDescription
6j7t-assembly1_A 1.00 1.00 2.0e-51 sig 6j7t-assembly1_A Crystal structure of toxin TglT (unusual type guanylyltransferase-like toxin, Rv1045) mutant D82A from Mycobacterium tuberculosis
7c46-assembly1_A 1.00 1.00 8.5e-52 sig 7c46-assembly1_A Crystal Structure of Rv1045 toxin point variant K189A
6j7r-assembly1_A 1.00 0.99 7.0e-50 sig 6j7r-assembly1_A Crystal structure of toxin TglT (unusual type guanylyltransferase-like toxin, Rv1045) mutant S78A co-expressed with TakA from Mycobacterium tuberculosis
6y5u-assembly1_A 1.00 0.99 4.0e-50 sig 6y5u-assembly1_A MenT3 (aka TglT), nucleotidyltransferase toxin Rv1045 from Mycobacterium tuberculosis
8xhr-assembly1_A 1.00 0.98 1.1e-49 sig 8xhr-assembly1_A Crystal structure of Mycobacterium tuberculosis MenT3 bound with CTP

Foldseek search of the AlphaFold DB model (mean pLDDT 95.8, 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 2

Upstream (5' on genome)Rv1044 (+ strand, -4 bp gap)
Downstream (3' on genome)Rv1047 (+ strand, 868 bp gap)
Predicted operon Rv1044 · Rv1045

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 (2 TF) Rv0023 (represses) · Rv0047c (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: Rv2209 (integral membrane protein), high confidence from genomic context alone (score 747 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.

PartnerProductScoreNo text-miningChannels (≥400)
Rv1044 hyp hypothetical protein 999 990 ctx neighborhood:801 cooccurence:758 coexpression:817 textmining:913
Rv2209 integral membrane protein 746 747 ctx cooccurence:745
Rv0355c PPE8 PPE family protein PPE8 746 747 ctx cooccurence:746
Rv3350c PPE56 PPE family protein PPE56 746 746 ctx cooccurence:745
Rv3347c PPE55 PPE family protein PPE55 742 742 ctx cooccurence:741
Rv1452c PE_PGRS28 PE-PGRS family protein PE_PGRS28 741 741 ctx cooccurence:741
Rv1917c PPE34 PPE family protein PPE34 734 734 ctx cooccurence:734
Rv3343c PPE54 PPE family protein PPE54 732 733 ctx cooccurence:730
Rv0304c PPE5 PPE family protein PPE5 727 727 ctx cooccurence:727
Rv1004c membrane protein 727 727 ctx cooccurence:727
Rv2490c PE_PGRS43 PE-PGRS family protein PE_PGRS43 721 721 ctx cooccurence:721
Rv1651c PE_PGRS30 PE-PGRS family protein PE_PGRS30 718 718 ctx cooccurence:718
Rv1753c PPE24 PPE family protein PPE24 712 713 ctx cooccurence:712
Rv0613c hyp hypothetical protein 709 709 ctx cooccurence:709
Rv2082 hyp hypothetical protein 709 709 ctx cooccurence:709

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: nucleotidyl transferase AbiEii/AbiGii toxin family protein
  • Pfam (hmmscan --cut_ga): AbiEii PF08843.18 (E=1e-19)
  • (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_215561.1)
  • Domains: Pfam-A via hmmscan --cut_ga — AbiEii (PF08843.18)
  • 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 2DQGD
  • Curated reference: UniProt P96356 (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 95.8)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 92 functional partner(s); context anchor Rv2209
  • 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
  • Experimental structures: PDBe/SIFTS UniProt→PDB mapping (Dana et al. 2019, doi:10.1093/nar/gky1114)
  • 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)
  • 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_001122|Rv1045|
MTKPYSSPPTNLRSLRDRLTQVAERQGVVFGRLQRHVAMIVVAQFAATLTDDTGAPLLLVKGGSSLELRRGIPDSRTSKDFDTVARRDIELIHEQLADAGETGWEGFTAIFTAPEEIDVPGMPVKPRRFTAKLSYRGRAFATVPIEVSSVEAGNADQFDTLTSDALGLVGVPAAVAVPCMTIPWQIAQKLHAVTAVLEEPKVNDRAHDLVDLQLLEGLLLDADLMPTRSACIAIFEARAQHPWPPRVATLPHWPLIYAGALEGLDHLELARTVDAAAQAVQRFVARIDRATKR