mmpR5 Family assigned · medium auto-curated

H37Rv Rv0678 · MTBC0 mtbc0_000717 · 165 aa · 783076–783573 MTBC0 (+) · RefSeq NP_215192.1

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-annotationsiderophore transport transcriptional regulator MmpR5
Revised (this work)Siderophore transport transcriptional regulator MmpR5. Pfam: HTH_MmpR5 (PF27059.1).
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) 57 publications

Found under: H37Rv (57).

57 TB publications mention this gene. 57 publication(s) mention this gene (title/abstract), verified against the text. The atlas states the function; these are the primary sources that discuss it.

Most recent 5 of 57.
PublicationDate
Comparative in vitro antimicrobial susceptibility profiles of clofazimine and pyrifazimine against clinical isolates of Mycobacterium tuberculosis in southwest China. doi:10.1128/spectrum.02664-25 2026
A Case of Transmission of Bedaquiline- and Linezolid-Resistant Tuberculosis. doi:10.3390/ijms27114912 2026
Phenotypic drug susceptibility testing and genotypic characterization of Bedaquiline resistance in drug resistant Mycobacteriumtuberculosis. doi:10.1016/j.ijmmb.2026.101163 2026
Targeted next-generation sequencing implementation in Eswatini identifies rifampicin and bedaquiline resistance undetected by routine diagnostic testing. doi:10.1038/s41467-026-73551-w 2026
Bedaquiline resistance-associated genetic mutations and minimum inhibitory concentrations in drug-resistant tuberculosis clinical isolates from Limpopo province, South Africa. doi:10.3389/fmicb.2026.1803115 2026

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.

Conditional expression context (iModulons)

Member of 1 independently-modulated gene set(s): Rv2488c (Rv2488c).

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 0.59 (95% CI -0.59 to 2.44). 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), COG category). 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 Mb0697 · 99.4% identity
M. marinum MMAR_1007 · 83.0% identity
M. orygis RJtmp_000715 · 99.4% 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 I6Y8F7 SwissProt · reviewed · Evidence at protein level
UniProt nameHTH-type transcriptional regulator MmpR5
Curated functionControls the expression level of the Mmps2-MmpL2, MmpS4-MmpL4, and MmpS5-MmpL5 transport systems. Also controls its own expression. Acts by binding directly to the promoter regions.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category K Transcription
eggNOG descriptionregulation of RNA biosynthetic process
Orthologous groupCOG1510

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, 1 frameshift
Disruption 1 distinct premature-stop/frameshift site(s); most common in 0.16% of strains (234) · 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) Corynebacteriales

M. canettii dN/dS (deep-divergence selection) 0.0 (low power) · 4 consensus substitution(s)
low power (4 canettii-consensus substitution(s)); present in M. canettii but dN/dS not reliable
Genus-wide presence (~53 non-MTBC Mycobacterium) present in 23/53 (43%) · mean identity 49.8% · 1/4 closest MTBAP relatives
present in a subset of the genus (23/53 NTM; in 1 of the 4 closest MTBAP relatives) — partial/intermediate conservation
Phylostratum (deepest detected homolog) MTBC-specific Mycobacterium Mycobacteriaceae Corynebacteriales Actinomycetia Bacteria
detected in 2/13 non-Mycobacterium reference genomes (down to Corynebacteriales) · mean identity 32.0%
detected across the order Corynebacteriales (Corynebacterium/Nocardia/Rhodococcus/…) but not in more distant Actinomycetia — a Corynebacteriales-level 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) 5 in the ORF — 0 in the essential state, 0 growth-defect, 5 non-essential, 0 growth-advantage. Saturation 1.000, mean read count 315.2. A region of the protein devoid of TA sites is invisible to this assay: nothing can be inferred about it, in either direction.
CaveatRead with some caution: only 5 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 5 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.

Conditional fitness (RB-TnSeq, 95 conditions) stress

ConditionGroupDirectionlog2 fitnesst
Econazole nitrate salt stress mutant enriched (loss advantageous) 2.365 13.82
Clofazimine stress mutant enriched (loss advantageous) 2.116 9.804

Randomly-barcoded transposon screen across 95 carbon/nitrogen sources, pH, stressors and antibiotics (2 condition-specific phenotype(s) for this gene). A conditional fitness phenotype is a context lead, not a proven function, and never changes the verdict here. Note the blind spot: RB-TnSeq cannot measure essential genes. Source: RB-TnSeq 95-condition barcoded transposon screen, Mtb (PLoS Biol 2026, doi:10.1371/journal.pbio.3003529).

Drug resistance (WHO catalogue) bedaquilineclofazimine

bedaquiline226 catalogued resistance-associated variant(s)
clofazimine175 catalogued resistance-associated variant(s)

This gene carries mutations classed Associated with resistance (WHO grade 1–2) in the consolidated catalogue (WHO 2nd ed. 2023 + tb-profiler). Only the R-associated tier is shown; "uncertain" and empirical-only signals are excluded. Test a specific strain or variant with the resistance tester. Research context, not a clinical diagnostic.

Proteomics (mass spectrometry) detected

MS detectiondetected in 15 of 16 independent MS datasets
Integrated abundance477.0 ppm · rank 423/3519 (88.0th 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)

Length165 aa
Molecular weight18.4 kDa
Theoretical pI4.95
GRAVY-0.36 (hydrophilic)
Aliphatic index82.3
Aromaticity0.067
Instability index56.8 (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
HTH_MmpR5PF27059.1 7.0e-1598–159 MmpR5-like MarR family transcriptional regulator

Experimental structures (Protein Data Bank) 1 solved

PDBMethodResolutionCoverage
4nb5 X-ray diffraction 1.641 Å 99%

Experimentally solved structures mapped from the UniProt accession via PDBe/SIFTS (1 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 92.0

PDB hitprobTM-scoreE-valueDescription
4nb5-assembly1_C 1.00 0.98 3.4e-24 sig 4nb5-assembly1_C Crystal Structure of a transcriptional regulator
1ku9-assembly1_B 1.00 0.69 1.0e-07 sig 1ku9-assembly1_B X-ray Structure of a Methanococcus jannaschii DNA-Binding Protein: Implications for Antibiotic Resistance in Staphylococcus aureus
5jbr-assembly1_B 1.00 0.65 2.4e-07 sig 5jbr-assembly1_B Crystal structure of uncharacterized protein Bcav_2135 from Beutenbergia cavernae
8ylg-assembly1_B 1.00 0.52 4.5e-04 sig 8ylg-assembly1_B Crystal structure of Burkholderia thailandensis MftR in complex with operator DNA
4ld5-assembly3_G 1.00 0.49 3.8e-04 sig 4ld5-assembly3_G Crystal structure of MepR Q18P mutant from multidrug resistant S. aureus clinical isolate

Foldseek search of the AlphaFold DB model (mean pLDDT 92.0, 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)

Upstream (5' on genome)mmpS5 (- strand, 84 bp gap)
Downstream (3' on genome)Rv0679c (- strand, 55 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).

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

Regulated by (1 TF) mmpR5 (activates)
Regulonthis transcription factor regulates 212 target gene(s)

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: mmpL5 (transmembrane transport protein MmpL5), high confidence from genomic context alone (score 915 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.

PartnerProductScoreNo text-miningChannels (≥400)
Rv0676c mmpL5 transmembrane transport protein MmpL5 989 915 ctx neighborhood:571 coexpression:810 textmining:883
Rv0677c mmpS5 membrane protein MmpS5 974 814 ctx neighborhood:601 coexpression:553 textmining:870
Rv3160c TetR family transcriptional regulator 799 799 coexpression:799
Rv3066 DeoR family transcriptional regulator 812 773 coexpression:739
Rv1152 transcriptional regulator 580 580 coexpression:580
Rv0792c transcriptional regulator 474 474 coexpression:474
Rv1733c transmembrane protein 426 426 ctx cooccurence:423
Rv1404 transcriptional regulator 474 326
Rv1455 hyp hypothetical protein 416 234
Rv3855 ethR HTH-type transcriptional repressor EthR 442 212
Rv1453 transcriptional activator protein 533 85 textmining:511
Rv1049 transcriptional repressor 811 80 textmining:803
Rv0880 HTH-type transcriptional regulator 559 65 textmining:548
Rv2043c pncA pyrazinamidase/nicotinamidase PncA 572 64 textmining:562
Rv1173 fbiC FO synthase 663 58 textmining:657

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: siderophore transport transcriptional regulator MmpR5
  • Pfam (hmmscan --cut_ga): HTH_MmpR5 PF27059.1 (E=7e-15)
  • (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_215192.1)
  • Domains: Pfam-A via hmmscan --cut_ga — HTH_MmpR5 (PF27059.1)
  • 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 COG1510
  • Curated reference: UniProt I6Y8F7 (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 92.0)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 30 functional partner(s); context anchor mmpL5
  • 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)
  • Drug resistance: consolidated catalogue, WHO 2nd ed. 2023 (9789240082410) + tb-profiler; only the resistance-associated tier (grade 1–2) is surfaced
  • 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_000717|Rv0678|mmpR5
MSVNDGVDQMGAEPDIMEFVEQMGGYFESRSLTRLAGRLLGWLLVCDPERQSSEELATALAASSGGISTNARMLIQFGFIERLAVAGDRRTYFRLRPNAFAAGERERIRAMAELQDLADVGLRALGDAPPQRSRRLREMRDLLAYMENVVSDALGRYSQRTGEDD