cobIJ Resolved · high auto-curated

H37Rv Rv2066 · MTBC0 mtbc0_002200 · 508 aa · 2351788–2353314 (+) · RefSeq NP_216582.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)bifunctional S-adenosyl-L-methionine-precorrin-2 methyl transferase/precorrin-3 methylase
MTBC0 PGAP re-annotationprecorrin-2 C(20)-methyltransferase
Revised (this work)Precorrin-2 C(20)-methyltransferase. Pfam: TP_methylase (PF00590.26).

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

Curated reference (UniProt)

UniProt P9WGB3 SwissProt · reviewed · Evidence at protein level
UniProt nameCobalamin biosynthesis protein CobIJ [Includes: Precorrin-2 C(20)-methyltransferase
EC (curated) EC 2.1.1.130, EC 2.1.1.131
Curated functionMethylates precorrin-2 at the C-20 position to produce precorrin-3A.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category H Coenzyme transport and metabolism
Preferred namecobIJ
eggNOG descriptionBelongs to the precorrin methyltransferase family
Orthologous groupCOG1010
EC number EC 2.1.1.130, EC 2.1.1.131
KEGG orthology K05934, K13540
KEGG pathways map00860, map01100
Gene Ontology (6) GO:0005575, GO:0005623, GO:0005886, GO:0016020, GO:0044464, GO:0071944

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 0.345 · purifying
Polymorphic sites (≥ 0.1% of strains) 12 synonymous, 11 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
TP_methylasePF00590.26 1.1e-416–219 Tetrapyrrole (Corrin/Porphyrin) Methylases

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

Closest characterised functional partner: cobM (precorrin-4 C(11)-methyltransferase), high confidence from genomic context alone (score 1000 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv2071c cobM precorrin-4 C(11)-methyltransferase 999 1000 ctx cooccurence:765 coexpression:999 database:900 textmining:554
Rv2065 cobH precorrin-8X methylmutase 999 1000 ctx neighborhood:881 fusion:897 cooccurence:774 coexpression:982 textmining:554
Rv2070c cobK precorrin-6A reductase 999 1000 ctx cooccurence:773 coexpression:999 textmining:554
Rv2072c cobL precorrin-6Y C(5,15)-methyltransferase 999 1000 ctx neighborhood:544 cooccurence:774 coexpression:997 textmining:850
Rv0255c cobQ1 cobyric acid synthase 999 999 ctx fusion:726 cooccurence:469 coexpression:990 textmining:596
Rv2064 cobG precorrin-3B synthase 998 997 ctx neighborhood:876 cooccurence:760 database:900 textmining:529
Rv2208 cobS adenosylcobinamide-GDP ribazoletransferase 991 982 coexpression:963 textmining:554
Rv2847c cysG multifunctional uroporphyrin-III C-methyltransferase/precorrin-2 oxidase/ferrochelatase 991 969 ctx neighborhood:544 database:900 textmining:745
Rv0511 hemD uroporphyrin-III C-methyltransferase 987 964 ctx neighborhood:544 database:900 textmining:660
Rv2423 hyp hypothetical protein 965 943 coexpression:932 textmining:418
Rv2062c cobN cobalamin biosynthesis protein CobN 969 926 ctx neighborhood:672 cooccurence:759 textmining:608
Rv2848c cobB cobyrinic acid A,C-diamide synthase 959 912 ctx cooccurence:755 coexpression:463 textmining:554
Rv2850c magnesium chelatase 858 838 ctx neighborhood:544 cooccurence:648
Rv2063A mazF7 mRNA interferase MazF7 792 792 ctx neighborhood:792
Rv2236c cobD cobalamin biosynthesis transmembrane protein CobD 940 786 ctx cooccurence:647 textmining:734

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: bifunctional S-adenosyl-L-methionine-precorrin-2 methyl transferase/precorrin-3 methylase
  • MTBC0 PGAP product: precorrin-2 C(20)-methyltransferase
  • Pfam (hmmscan --cut_ga): TP_methylase PF00590.26 (E=1e-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_216582.1)
  • Domains: Pfam-A via hmmscan --cut_ga — TP_methylase (PF00590.26)
  • 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 COG1010
  • Curated reference: UniProt P9WGB3 (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 — 67 functional partner(s); context anchor cobM
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_002200|Rv2066|cobIJ
MSARGTLWGVGLGPGDPELVTVKAARVIGEADVVAYHSAPHGHSIARGIAEPYLRPGQLEEHLVYPVTTEATNHPGGYAGALEDFYADATERIATHLDAGRNVALLAEGDPLFYSSYMHLHTRLTRRFNAVIVPGVTSVSAASAAVATPLVAGDQVLSVLPGTLPVGELTRRLADADAAVVVKLGRSYHNVREALSASGLLGDAFYVERASTAGQRVLPAADVDETSVPYFSLAMLPGGRRRALLTGTVAVVGLGPGDSDWMTPQSRRELAAATDLIGYRGYLDRVEVRDGQRRHPSDNTDEPARARLACSLADQGRAVAVVSSGDPGVFAMATAVLEEAEQWPGVRVRVIPAMTAAQAVASRVGAPLGHDYAVISLSDRLKPWDVIAARLTAAAAADLVLAIYNPASVTRTWQVGAMRELLLAHRDPGIPVVIGRNVSGPVSGPNEDVRVVKLADLNPAEIDMRCLLIVGSSQTRWYSVDSQDRVFTPRRYPEAGRATATKSSRHSD