Rv3818 Resolved · high auto-curated

H37Rv Rv3818 · MTBC0 mtbc0_004047 · 516 aa · 4306559–4308109 (+) · RefSeq NP_218335.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)hypothetical protein
MTBC0 PGAP re-annotationMBL fold metallo-hydrolase
Revised (this work)MBL fold metallo-hydrolase. Pfam: Lactamase_B_3 (PF13483.13), SCP2_Rv3818 (PF25451.2), Rieske (PF00355.33).

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

Curated reference (UniProt)

UniProt P9WH21 SwissProt · reviewed · Evidence at protein level
UniProt namePutative Rieske 2Fe-2S iron-sulfur protein Rv3818
EC (curated) EC 1.-.-.-

UniProt still lists this protein as Putative Rieske 2Fe-2S iron-sulfur protein Rv3818; the revised annotation above is ahead of the current UniProt record.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category P Inorganic ion transport and metabolism
eggNOG descriptionRieske 2Fe-2S
Orthologous groupCOG2146
KEGG orthology K14952
KEGG pathways map05152

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 0.315 · purifying
Polymorphic sites (≥ 0.1% of strains) 5 synonymous, 5 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.

Domains (Pfam, hmmscan --cut_ga)

PfamAccessioni-EvalueResiduesDescription
Lactamase_B_3PF13483.13 2.1e-062–73 Beta-lactamase superfamily domain
SCP2_Rv3818PF25451.2 1.4e-46332–450 Rv3818-like, SCP2-like domain
RieskePF00355.33 2.5e-08466–507 Rieske [2Fe-2S] domain

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

Closest characterised functional partner: Rv3817 (phosphotransferase), medium confidence from genomic context alone (score 671 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.

PartnerProductScoreNo text-miningChannels (≥400)
Rv3819 hyp hypothetical protein 970 970 ctx neighborhood:881 coexpression:761
Rv0688 ferredoxin reductase 730 714 coexpression:500 experimental:434
Rv0252 nirB nitrite reductase large subunit NirB 730 713 coexpression:498 experimental:434
Rv1869c reductase 730 713 coexpression:498 experimental:434
Rv0511 hemD uroporphyrin-III C-methyltransferase 747 710 coexpression:617
Rv2847c cysG multifunctional uroporphyrin-III C-methyltransferase/precorrin-2 oxidase/ferrochelatase 785 707 coexpression:647
Rv3817 phosphotransferase 671 671 ctx neighborhood:671
Rv0495c hyp hypothetical protein 644 644 ctx cooccurence:643
Rv1125 hyp hypothetical protein 630 611 ctx cooccurence:596
Rv2876 transmembrane protein 598 599 ctx cooccurence:539
Rv3035 hyp hypothetical protein 574 575 ctx cooccurence:568
Rv0331 dehydrogenase/reductase 595 570 experimental:484
Rv3813c hyp hypothetical protein 581 566 ctx neighborhood:565
Rv3647c hyp hypothetical protein 562 562 ctx cooccurence:562
Rv3816c acyltransferase 568 559 ctx neighborhood:559

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: MBL fold metallo-hydrolase
  • Pfam (hmmscan --cut_ga): Lactamase_B_3 PF13483.13 (E=2e-06), SCP2_Rv3818 PF25451.2 (E=1e-46), Rieske PF00355.33 (E=2e-08)
  • (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_218335.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Lactamase_B_3 (PF13483.13), SCP2_Rv3818 (PF25451.2), Rieske (PF00355.33)
  • 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 COG2146
  • Curated reference: UniProt P9WH21 (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 — 65 functional partner(s); context anchor Rv3817
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_004047|Rv3818|
MQVTSVGHAGFLIQTQAGSILCDPWVNPAYFASWFPFPDNSGLDWGALGECDYLYVSHLHKDHFDAENLRAHVNKDAVVLLPDFPVPDLRNELQKLGFHRFFETTDSVKHRLRGPNGDLDVMIIALRAPADGPIGDSALVVADGETTAFNMNDARPVDLDVLASEFGHIDVHMLQYSGAIWYPMVYDMPARAKDAFGAQKRQRQMDRARQYIAQVGATWVVPSAGPPCFLAPELRHLNDDGSDPANIFPDQMVFLDQMRAHGQDGGLLMIPGSTADFTGTTLNSLRHPLPAEQVEAIFTTDKAAYIADYADRMAPVLAAQKAGWAAAAGEPLLQPLRTLFEPIMLQSNEICDGIGYPVELAIGPETIVLDFPKRAVREPIPDERFRYGFAIAPELVRTVLRDNEPDWVNTIFLSTRFRAWRVGGYNEYLYTFFKCLTDERIAYADGWFAEAHDDSSSITLNGWEIQRRCPHLKADLSKFGVVEGNTLTCNLHGWQWRLDDGRCLTARGHQLRSSRP