cyp124 Resolved · high auto-curated

H37Rv Rv2266 · MTBC0 mtbc0_002408 · 428 aa · 2566209–2567495 MTBC0 (+) · RefSeq NP_216782.1

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)cytochrome P450 Cyp124
MTBC0 PGAP re-annotationmethyl-branched lipid omega-hydroxylase Cyp124
Revised (this work)Methyl-branched lipid omega-hydroxylase Cyp124. Pfam: p450 (PF00067.28).
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) 14 publications

14 TB publications mention this gene. 14 publication(s) discuss this gene (13 in a M. tuberculosis context, 3 in other mycobacteria — M. marinum (3)).

Most recent 5 of 14.
PublicationDate
Diverse ligands for mycobacterial CYP124 identified from plant and marine compounds. doi:10.1016/j.biochi.2026.02.019 2026
The bacterial cytochrome P450 (CYP) CYP125 enzymes can competitively oxidise sitosterol in the presence of cholesterol. doi:10.1039/d3cc02312e 2023
The oxidation of cholesterol derivatives by the CYP124 and CYP142 enzymes from Mycobacterium marinum. doi:10.1016/j.jsbmb.2023.106317 2023
The catalytic activity and structure of the lipid metabolizing CYP124 cytochrome P450 enzyme from Mycobacterium marinum. doi:10.1016/j.abb.2023.109554 2023
Structural insights into the effects of glycerol on ligand binding to cytochrome P450. doi:10.1107/S2059798322011019 2023

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.

CRISPRi vulnerability

Vulnerability index 0.85 (95% CI -1.53 to 4.62). 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 functionCytochromes P450 are a group of heme-thiolate monooxygenases. They oxidize a variety of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics.
Mycobrowser EC 1.14.-.- · superseded EC numbering; the atlas uses the current class (1.14.15.14, 1.14.15.28)

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 Mb2289 · 100.0% identity
M. marinum MMAR_3361 · 85.2% identity
M. smegmatis MSMEG_3551 · 74.9% identity
M. orygis RJtmp_002342 · 100.0% 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 P9WPP3 SwissProt · reviewed · Evidence at protein level
UniProt nameMethyl-branched lipid omega-hydroxylase
EC (curated) EC 1.14.15.14, EC 1.14.15.28
Curated functionPrimarily hydroxylates the omega-carbon of a number of methyl-branched lipids, including (2E,6E)-farnesol, phytanate, geranylgeraniol, 15-methylpalmitate and (2E,6E)-farnesyl diphosphate. Also catalyzes the sequential oxidation of the terminal methyl of cholest-4-en-3-one into (25R)-26-hydroxycholest-4-en-3-one (alcohol), (25R)-26-oxocholest-4-en-3-one (aldehyde), to finally yield the carboxylic acid (25R)-3-oxocholest-4-en-26-oate. Cyp124 catalyzes preferentially the oxidation of (25R)-26-hydroxycholest-4-en-3-one diastereomer. Also able to sequentially oxidize cholesterol itself, not only ch.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category Q Secondary metabolites biosynthesis, transport and catabolism
Preferred namecyp124A1
eggNOG descriptioncytochrome p450
Orthologous groupCOG2124
EC number EC 1.14.15.14
KEGG orthology K20497
Gene Ontology (60) GO:0000166, GO:0003674, GO:0003824, GO:0004497, GO:0005488, GO:0006066, GO:0006082, GO:0006629, GO:0006631, GO:0006706, GO:0006707, GO:0008150 +48 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 2.925 · diversifying/relaxed
Polymorphic sites (≥ 0.1% of strains) 1 synonymous, 9 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 52/53 (98%) · mean identity 79.1% · 4/4 closest MTBAP relatives
conserved across the genus (present in 52/53 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 7/13 non-Mycobacterium reference genomes (down to Bacteria) · mean identity 38.6%
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) 17 in the ORF — 0 in the essential state, 0 growth-defect, 17 non-essential, 0 growth-advantage. Saturation 0.941, mean read count 120.1875. 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 7 of 16 independent MS datasets
Integrated abundance3.72 ppm · rank 3033/3519 (13.8th 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)

Length428 aa
Molecular weight47.8 kDa
Theoretical pI5.1
GRAVY-0.199 (hydrophilic)
Aliphatic index87.6
Aromaticity0.091
Instability index45.0 (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
p450PF00067.28 1.3e-12303–393 Cytochrome P450

Experimental structures (Protein Data Bank) 9 solved

PDBMethodResolutionCoverage
7zb9 X-ray diffraction 1.15 Å 100%
6t0h X-ray diffraction 1.18 Å 100%
6t0k X-ray diffraction 1.18 Å 100%
6t0j X-ray diffraction 1.25 Å 100%
6t0g X-ray diffraction 1.3 Å 100%
2wm5 X-ray diffraction 1.5 Å 100%
6t0f X-ray diffraction 1.65 Å 100%
6t0l X-ray diffraction 1.8 Å 100%

Experimentally solved structures mapped from the UniProt accession via PDBe/SIFTS (9 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 92.4

PDB hitprobTM-scoreE-valueDescription
6t0l-assembly1_A 1.00 0.98 1.6e-64 sig 6t0l-assembly1_A Crystal structure of CYP124 in complex with inhibitor compound 5'
2wm5-assembly1_A 1.00 0.98 3.5e-62 sig 2wm5-assembly1_A X-ray structure of the substrate-free Mycobacterium tuberculosis cytochrome P450 CYP124
6t0g-assembly1_A 1.00 0.98 3.2e-62 sig 6t0g-assembly1_A Crystal structure of CYP124 in complex with vitamin D3
8fkb-assembly1_A 1.00 0.98 4.2e-58 sig 8fkb-assembly1_A X-ray crystal structure of CYP124A1 from Mycobacterium Marinum bound to Farnesol
6bld-assembly1_A 1.00 0.92 1.1e-34 sig 6bld-assembly1_A Mycobacterium marinum cytochrome P450 CYP268A2 in complex with pseudoionone

Foldseek search of the AlphaFold DB model (mean pLDDT 92.4, 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)Rv2265 (+ strand, 174 bp gap)
Downstream (3' on genome)Rv2267c (- strand, 253 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).

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.

PartnerProductScoreNo text-miningChannels (≥400)
Rv3800c pks13 exp polyketide synthase 943 938 experimental:891
Rv2380c mbtE exp peptide synthetase 809 800 experimental:689
Rv1937 exp oxygenase 812 785 experimental:478
Rv2776c oxidoreductase 796 783
Rv0719 rplF exp 50S ribosomal protein L6 689 689 experimental:412 database:493
Rv1629 polA exp DNA polymerase I 704 686 database:638
Rv2946c pks1 exp polyketide synthase 715 680 experimental:460
Rv3554 fdxB electron transfer protein FdxB 703 666
Rv2932 ppsB exp phthiocerol synthesis polyketide synthase type I PpsB 681 661 experimental:460
Rv3825c pks2 phthioceranic/hydroxyphthioceranic acid synthase 694 660
Rv2940c mas multifunctional mycocerosic acid synthase 692 658
Rv2933 ppsC phthiocerol synthesis polyketide synthase type I PpsC 692 658
Rv1527c pks5 polyketide synthase 692 658
Rv2048c pks12 polyketide synthase 692 658
Rv3230c stearoyl-CoA 9-desaturase electron transfer protein 665 645

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: cytochrome P450 Cyp124
  • MTBC0 PGAP product: methyl-branched lipid omega-hydroxylase Cyp124
  • Pfam (hmmscan --cut_ga): p450 PF00067.28 (E=1e-12)
  • (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_216782.1)
  • Domains: Pfam-A via hmmscan --cut_ga — p450 (PF00067.28)
  • 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 COG2124
  • Curated reference: UniProt P9WPP3 (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 92.4)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 130 functional partner(s)
  • 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)
  • 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_002408|Rv2266|cyp124
MGLNTAIATRVNGTPPPEVPIADIELGSLDFWALDDDVRDGAFATLRREAPISFWPTIELPGFVAGNGHWALTKYDDVFYASRHPDIFSSYPNITINDQTPELAEYFGSMIVLDDPRHQRLRSIVSRAFTPKVVARIEAAVRDRAHRLVSSMIANNPDRQADLVSELAGPLPLQIICDMMGIPKADHQRIFHWTNVILGFGDPDLATDFDEFMQVSADIGAYATALAEDRRVNHHDDLTSSLVEAEVDGERLSSREIASFFILLVVAGNETTRNAITHGVLALSRYPEQRDRWWSDFDGLAPTAVEEIVRWASPVVYMRRTLTQDIELRGTKMAAGDKVSLWYCSANRDESKFADPWTFDLARNPNPHLGFGGGGAHFCLGANLARREIRVAFDELRRQMPDVVATEEPARLLSQFIHGIKTLPVTWS