rpsL Resolved · high auto-curated

H37Rv Rv0682 · MTBC0 mtbc0_000721 · 124 aa · 785646–786020 MTBC0 (+) · RefSeq NP_215196.1

Genomic neighbourhood (genome browser)

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+ strand − strand end (Rv0670) — requalified: deoxyribonuclease IV lpqP (Rv0671) — family_assigned: PHB depolymerase family esterase lpqP fadE8 (Rv0672) — family_assigned: acyl-CoA dehydrogenase family protein fadE8 echA4 (Rv0673) — family_assigned: crotonase/enoyl-CoA hydratase family protein echA4 Rv0674 (Rv0674) — family_assigned: PaaX family transcriptional regulator C-terminal domain-cont mmpL5 (Rv0676c) — requalified: siderophore RND transporter MmpL5 mmpL5 mmpS5 (Rv0677c) — requalified: siderophore transporter accessory protein MmpS5 mmpR5 (Rv0678) — family_assigned: siderophore transport transcriptional regulator MmpR5 Rv0679c (Rv0679c) — family_assigned: DUF3060 domain-containing protein Rv0680c (Rv0680c) — dark: DUF3060 domain-containing protein Rv0681 (Rv0681) — family_assigned: TetR/AcrR family transcriptional regulator rpsL (Rv0682) — requalified: 30S ribosomal protein S12 Rv0686 (Rv0686) — family_assigned: SHOCT domain-containing protein Rv0687 (Rv0687) — family_assigned: Rv0687 family mycofactocin-dependent SDR oxidoreductase Rv0687 Rv0688 (Rv0688) — requalified: FAD/NAD(P)-binding oxidoreductase Rv0688 Rv0690c (Rv0690c) — family_assigned: DUF2332 domain-containing protein Rv0690c mftR (Rv0691c) — family_assigned: mycofactocin system transcriptional regulator mftB (Rv0692) — requalified: mycofactocin biosynthesis chaperone MftB mftC (Rv0693) — requalified: mycofactocin radical SAM maturase mftC mftD (Rv0694) — requalified: pre-mycofactocin synthase MftD 776 kb 780 kb 784 kb 788 kb 792 kb 796 kb

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)30S ribosomal protein S12
MTBC0 PGAP re-annotation30S ribosomal protein S12
Revised (this work)30S ribosomal protein S12. Pfam: Ribosom_S12_S23 (PF00164.32).
Functional category (TubercuList)information pathways

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) 244 publications

244 TB publications mention this gene. 244 publication(s) discuss this gene (229 in a M. tuberculosis context, 16 in other mycobacteria — M. smegmatis (13), M. abscessus (2), M. leprae (2), M. marinum (1)).

Most recent 5 of 244.
PublicationDate
Analysis of Drug Resistance Characteristics and Risk Factors of Cavitary Tuberculosis Based on Whole Genome Sequencing and Machine Learning. doi:10.1093/ofid/ofag328 2026
Effects of nanozyme on environmental fate and dissemination of antibiotic resistance genes in anaerobically digested sludge. doi:10.1016/j.biortech.2026.134325 2026
Investigation of Gene Regions Responsible for Drug Resistance in Clinical Isolates of Mycobacterium tuberculosis Complex Resistant to at Least Two First-Line Anti-Tuberculosis Drugs. doi:10.3390/pathogens15020222 2026
In Silico Design of gRNA for CRISPR System for Detection of Multidrug Resistant Tuberculosis Using Indian Mycobacterium tuberculosis Genomes: A Computational Study. doi:10.7759/cureus.101851 2026
First insight of characteristics and prediction of Mycobacterium tuberculosis drug resistance by whole genome sequencing in Fujian Province, China. doi:10.1038/s41598-026-40398-6 2026

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) co-directional · 0 % of gene

NeighbourrpsG (Rv0683, + 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): Unc_4.

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 -15.36 (95% CI -16.87 to -13.84). 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 functionProtein S12 is involved in the translation initiation step.

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 Mb0701 · 100.0% identity
M. leprae ML1880c · 97.6% identity
M. marinum MMAR_1011 · 99.2% identity
M. smegmatis MSMEG_1398 · 99.2% identity
M. orygis RJtmp_000719 · 100.0% identity
M. abscessus MAB_3851c · 96.7% 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 P9WH63 SwissProt · reviewed · Evidence at protein level
UniProt nameSmall ribosomal subunit protein uS12
Curated functionWith S4 and S5 plays an important role in translational accuracy..; FUNCTION: Interacts with and stabilizes bases of the 16S rRNA that are involved in tRNA selection in the A site and with the mRNA backbone. Located at the interface of the 30S and 50S subunits, it traverses the body of the 30S subunit contacting proteins on the other side and probably holding the rRNA structure together. The combined cluster of proteins S8, S12 and S17 appears to hold together the shoulder and platform of the 30S subunit.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category J Translation, ribosomal structure and biogenesis
Preferred namerpsL
eggNOG descriptionInteracts with and stabilizes bases of the 16S rRNA that are involved in tRNA selection in the A site and with the mRNA backbone. Located at the interface of the 30S and 50S subunits, it traverses the body of the 30S subunit contacting proteins on the other side and probably holding the rRNA structure together. The combined cluster of proteins S8, S12 and S17 appears to hold together the shoulder and platform of the 30S subunit
Orthologous groupCOG0048
KEGG orthology K02950
KEGG pathways map03010
KEGG modules M00178, M00179
Gene Ontology (44) GO:0003674, GO:0003735, GO:0005198, GO:0005575, GO:0005622, GO:0005623, GO:0005737, GO:0005840, GO:0006412, GO:0006518, GO:0006807, GO:0008150 +32 more

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 0.335 · purifying
Polymorphic sites (≥ 0.1% of strains) 3 synonymous, 3 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 98.8% · 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 13/13 non-Mycobacterium reference genomes (down to Bacteria) · mean identity 87.8%
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) essential

DeJesus 2017 callES · essential
What the call meansessential: insertions absent across the whole ORF
TA sites (Himar1) 8 in the ORF — 8 in the essential state, 0 growth-defect, 0 non-essential, 0 growth-advantage. Saturation 0.125, mean read count 1. 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 8 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 8 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.

Drug resistance (WHO catalogue) streptomycin

streptomycin8 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 11 of 16 independent MS datasets
Integrated abundance984.0 ppm · rank 234/3519 (93.4th 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)

Length124 aa
Molecular weight13.8 kDa
Theoretical pI11.37
GRAVY-0.814 (hydrophilic)
Aliphatic index76.9
Aromaticity0.032
Instability index31.9 (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
Ribosom_S12_S23PF00164.32 3.9e-4118–123 Ribosomal protein S12/S23

Experimental structures (Protein Data Bank) 10 solved

PDBMethodResolutionCoverage
7sfr Electron Microscopy 2.6 Å 100%
7kgb Electron Microscopy 2.7 Å 100%
7mt7 Electron Microscopy 2.71 Å 100%
7mt2 Electron Microscopy 2.76 Å 100%
7msm Electron Microscopy 2.79 Å 100%
7mt3 Electron Microscopy 2.8 Å 100%
7msc Electron Microscopy 2.97 Å 100%
7msz Electron Microscopy 3.1 Å 100%

Experimentally solved structures mapped from the UniProt accession via PDBe/SIFTS (10 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 95.5

PDB hitprobTM-scoreE-valueDescription
8wib-assembly1_m 1.00 0.99 2.3e-21 sig 8wib-assembly1_m Cryo- EM structure of Mycobacterium smegmatis 70S ribosome, E- tRNA and RafH.
8cwo-assembly1_L 1.00 0.99 3.8e-21 sig 8cwo-assembly1_L Cutibacterium acnes 30S ribosomal subunit with Sarecycline bound, body domain only in the local refined map
7msz-assembly1_l 1.00 0.98 2.0e-19 sig 7msz-assembly1_l Mtb 70SIC in complex with MtbEttA at Trans_R1 state
8rdw-assembly1_L6 1.00 0.99 8.2e-19 sig 8rdw-assembly1_L6 Cryo-EM structure of P. urativorans 70S ribosome in complex with hibernation factor Balon and EF-Tu(GDP) (structure 3).
8ced-assembly1_L 1.00 0.98 2.3e-18 sig 8ced-assembly1_L Rnase R bound to a 30S degradation intermediate (State I - head-turning)

Foldseek search of the AlphaFold DB model (mean pLDDT 95.5, 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)Rv0681 (+ strand, 248 bp gap)
Downstream (3' on genome)rpsG (+ strand, -1 bp gap)
Predicted operon rpsL · rpsG

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).

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: rpsK (30S ribosomal protein S11), high confidence from genomic context alone (score 1000 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv0717 rpsN1 exp 30S ribosomal protein S14 999 1000 coexpression:734 experimental:999 database:662
Rv1643 rplT exp 50S ribosomal protein L20 999 1000 coexpression:861 experimental:999
Rv3442c rpsI exp 30S ribosomal protein S9 999 1000 coexpression:861 experimental:999 database:844 textmining:516
Rv0700 rpsJ exp 30S ribosomal protein S10 999 1000 coexpression:967 experimental:999 database:844 textmining:614
Rv0706 rplV exp 50S ribosomal protein L22 999 1000 coexpression:888 experimental:999
Rv3459c rpsK exp 30S ribosomal protein S11 999 1000 ctx cooccurence:512 coexpression:968 experimental:999 database:844
Rv0723 rplO exp 50S ribosomal protein L15 999 1000 coexpression:865 experimental:999
Rv2442c rplU exp 50S ribosomal protein L21 999 1000 coexpression:864 experimental:999
Rv0707 rpsC exp 30S ribosomal protein S3 999 1000 ctx cooccurence:473 coexpression:864 experimental:999 database:844 textmining:512
Rv0722 rpmD exp 50S ribosomal protein L30 999 1000 coexpression:863 experimental:999 textmining:451
Rv0056 rplI exp 50S ribosomal protein L9 999 1000 coexpression:794 experimental:999
Rv0702 rplD exp 50S ribosomal protein L4 999 1000 coexpression:958 experimental:999 database:844
Rv0719 rplF exp 50S ribosomal protein L6 999 1000 ctx cooccurence:422 coexpression:905 experimental:999
Rv3443c rplM exp 50S ribosomal protein L13 999 1000 coexpression:863 experimental:999 textmining:625
Rv3456c rplQ exp 50S ribosomal protein L17 999 1000 coexpression:946 experimental:999

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: 30S ribosomal protein S12
  • MTBC0 PGAP product: 30S ribosomal protein S12
  • Pfam (hmmscan --cut_ga): Ribosom_S12_S23 PF00164.32 (E=4e-41)
  • (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_215196.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Ribosom_S12_S23 (PF00164.32)
  • 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 COG0048
  • Curated reference: UniProt P9WH63 (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 95.5)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 308 functional partner(s); context anchor rpsK
  • 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)
  • 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_000721|Rv0682|rpsL
MPTIQQLVRKGRRDKISKVKTAALKGSPQRRGVCTRVYTTTPKKPNSALRKVARVKLTSQVEVTAYIPGEGHNLQEHSMVLVRGGRVKDLPGVRYKIIRGSLDTQGVKNRKQARSRYGAKKEKG