Rv1558 Resolved · high auto-curated

H37Rv Rv1558 · MTBC0 mtbc0_001666 · 148 aa · 1774911–1775357 (+) · RefSeq NP_216074.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)hypothetical protein
MTBC0 PGAP re-annotationF420H(2)-dependent quinone reductase
Revised (this work)F420H(2)-dependent quinone reductase. Pfam: F420H2_quin_red (PF04075.21).

Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.

Curated reference (UniProt)

UniProt P9WP11 SwissProt · reviewed · Evidence at protein level
UniProt nameF420H(2)-dependent quinone reductase Rv1558
EC (curated) EC 1.1.98.-
Curated functionInvolved in a F420-dependent anti-oxidant mechanism that protects M.tuberculosis against oxidative stress and bactericidal agents. Catalyzes the F420H(2)-dependent two-electron reduction of quinones to dihydroquinones, thereby preventing the formation of cytotoxic semiquinones obtained by the one-electron reduction pathway. In vitro, catalyzes the reduction of menadione to menadiol; since menaquinone is the sole quinone electron carrier in the respiratory chain in M.tuberculosis, the physiological electron acceptor for Fqr-mediated F420H(2) oxidation is therefore likely to be the endogenous me.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category K Transcription
eggNOG descriptionnitroreductase
Orthologous groupCOG1846
Gene Ontology (24) GO:0003674, GO:0005488, GO:0005575, GO:0005618, GO:0005623, GO:0005886, GO:0008150, GO:0008152, GO:0016020, GO:0030312, GO:0031406, GO:0036094 +12 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 0.107 · strong purifying
Polymorphic sites (≥ 0.1% of strains) 3 synonymous, 1 missense, 0 nonsense, 1 frameshift
Disruption 1 distinct premature-stop/frameshift site(s); most common in 0.19% of strains (270) · 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.

Domains (Pfam, hmmscan --cut_ga)

PfamAccessioni-EvalueResiduesDescription
F420H2_quin_redPF04075.21 5.9e-5814–143 F420H(2)-dependent quinone reductase

Functional interaction network (STRING v12, guilt-by-association)

Closest characterised functional partner: mmpL6 (transmembrane transport protein MmpL6), high confidence from genomic context alone (score 868 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.

PartnerProductScoreNo text-miningChannels (≥400)
Rv1557 mmpL6 transmembrane transport protein MmpL6 868 868 ctx neighborhood:867
Rv1559 ilvA threonine dehydratase IlvA 841 835 ctx neighborhood:830
Rv0044c oxidoreductase 768 759 ctx cooccurence:758
Rv3261 fbiA 2-phospho-L-lactate transferase 835 751 ctx cooccurence:747
Rv0407 fgd1 F420-dependent glucose-6-phosphate dehydrogenase 949 745 ctx cooccurence:745 textmining:812
Rv3520c coenzyme F420-dependent oxidoreductase 750 741 ctx cooccurence:738
Rv3262 fbiB coenzyme F420:L-glutamate ligase 812 717 ctx cooccurence:707
Rv2983 cofC 2-phospho-L-lactate guanylyltransferase 773 702 ctx cooccurence:694
Rv0132c fgd2 F420-dependent glucose-6-phosphate dehydrogenase 704 693 ctx cooccurence:693
Rv1855c oxidoreductase 696 685 ctx cooccurence:682
Rv2951c phthiodiolone/phenolphthiodiolone dimycocerosates ketoreductase 744 665 ctx cooccurence:662
Rv3204 DNA-methyltransferase 656 656 ctx fusion:656
Rv0331 dehydrogenase/reductase 651 636 database:583
Rv3093c oxidoreductase 633 619 ctx cooccurence:619
Rv1561 vapC11 ribonuclease VapC11 566 566 ctx neighborhood:563

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 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: F420H(2)-dependent quinone reductase
  • Pfam (hmmscan --cut_ga): F420H2_quin_red PF04075.21 (E=6e-58)
  • (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_216074.1)
  • Domains: Pfam-A via hmmscan --cut_ga — F420H2_quin_red (PF04075.21)
  • 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 COG1846
  • Curated reference: UniProt P9WP11 (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)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 35 functional partner(s); context anchor mmpL6
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_001666|Rv1558|
MPLSGEYAPSPLDWSREQADTYMKSGGTEGTQLQGKPVILLTTVGAKTGKLRKTPLMRVEHDGQYAIVASLGGAPKNPVWYHNVVKNPRVELQDGTVTGDYDAREVFGDEKAIWWQRAVAVWPDYASYQTKTDRQIPVFVLTPVRAGG