spoU Resolved · high auto-curated

H37Rv Rv3366 · MTBC0 mtbc0_003581 · 154 aa · 3804445–3804909 (+) · RefSeq NP_217883.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)tRNA/rRNA methylase SpoU
MTBC0 PGAP re-annotationtRNA (cytidine(34)-2'-O)-methyltransferase
Revised (this work)TRNA (cytidine(34)-2'-O)-methyltransferase. Pfam: SpoU_methylase (PF00588.25).

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

Curated reference (UniProt)

UniProt O50394 TrEMBL · unreviewed · Evidence at protein level
UniProt namePutative tRNA
EC (curated) EC 2.1.1.207
Curated functionCould methylate the ribose at the nucleotide 34 wobble position in tRNA.

UniProt still lists this protein as Putative tRNA; the revised annotation above is ahead of the current UniProt record.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category J Translation, ribosomal structure and biogenesis
Preferred namespoU
eggNOG descriptionBelongs to the class IV-like SAM-binding methyltransferase superfamily. RNA methyltransferase TrmH family. TrmL subfamily
Orthologous groupCOG0219
EC number EC 2.1.1.207
KEGG orthology K03216

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 n/a
Polymorphic sites (≥ 0.1% of strains) 0 synonymous, 1 missense, 0 nonsense, 1 frameshift
Disruption 1 distinct premature-stop/frameshift site(s); most common in 0.11% of strains (156) · 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
SpoU_methylasePF00588.25 2.2e-292–142 SpoU rRNA Methylase family

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

Closest characterised functional partner: Rv3362c (ATP/GTP-binding protein), medium confidence from genomic context alone (score 495 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv3361c mfpA hyp hypothetical protein 547 548 ctx neighborhood:541
Rv3365c hyp hypothetical protein 529 529 ctx neighborhood:526
Rv2462c tig trigger factor 525 525
Rv3363c hyp hypothetical protein 523 523 ctx neighborhood:518
Rv3362c ATP/GTP-binding protein 494 495 ctx neighborhood:491
Rv3364c hyp hypothetical protein 493 492 ctx neighborhood:486
Rv2882c frr ribosome recycling factor 424 425 coexpression:422
Rv3367 PE_PGRS51 PE-PGRS family protein PE_PGRS51 410 410 ctx neighborhood:410
Rv1407 fmu 16S rRNA m5C967 methyltransferase 462 290
Rv0208c trmB tRNA (guanine-N(7)-)-methyltransferase 448 280
Rv0557 mgtA GDP-mannose-dependent alpha-mannosyltransferase 452 217
Rv2966c rsmD methyltransferase 830 153 textmining:808
Rv3442c rpsI 30S ribosomal protein S9 835 74 textmining:830
Rv2765 hydrolase 662 73 textmining:651
Rv1781c malQ 4-alpha-glucanotransferase 628 51 textmining:625

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: tRNA/rRNA methylase SpoU
  • MTBC0 PGAP product: tRNA (cytidine(34)-2'-O)-methyltransferase
  • Pfam (hmmscan --cut_ga): SpoU_methylase PF00588.25 (E=2e-29)
  • (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_217883.1)
  • Domains: Pfam-A via hmmscan --cut_ga — SpoU_methylase (PF00588.25)
  • 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 COG0219
  • Curated reference: UniProt O50394 (TrEMBL, unreviewed; 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 — 21 functional partner(s); context anchor Rv3362c
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003581|Rv3366|spoU
MFRLLFVSPRIAPNTGNAIRTCAATGCELHLVEPLGFDLSEPKLRRAGLDYHDLASVTVHASLAHAWEALSPARVFAFTAQATTLFTNVGYRAGDVLMFGPEPTGLDEATLADTHITGQVRIPMLAGRRSLNLSNAAAVAVYEAWRQHGFAGAV