cobQ2 Resolved · high auto-curated

H37Rv Rv3713 · MTBC0 mtbc0_003936 · 231 aa · 4182348–4183043 (+) · RefSeq NP_218230.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)cobyric acid synthase CobQ
MTBC0 PGAP re-annotationtype 1 glutamine amidotransferase
Revised (this work)Type 1 glutamine amidotransferase. Pfam: GATase_3 (PF07685.21).

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

Curated reference (UniProt)

UniProt I6XI14 TrEMBL · unreviewed · Evidence at protein level
UniProt nameLipid II isoglutaminyl synthase
EC (curated) EC 3.5.1.2, EC 6.3.5.13
Curated functionThe lipid II isoglutaminyl synthase complex catalyzes the formation of alpha-D-isoglutamine in the cell wall lipid II stem peptide. The GatD subunit catalyzes the hydrolysis of glutamine to glutamate and ammonia. The resulting ammonia molecule is channeled to the active site of MurT.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
Preferred namecobQ2
eggNOG descriptionglutamine amidotransferase
Orthologous groupCOG3442
KEGG orthology K07009

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 0.158 · strong purifying
Polymorphic sites (≥ 0.1% of strains) 5 synonymous, 2 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
GATase_3PF07685.21 3.1e-353–197 CobB/CobQ-like glutamine amidotransferase domain

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

Closest characterised functional partner: Rv3712 (ligase), high confidence from genomic context alone (score 1000 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv3712 ligase 999 1000 ctx neighborhood:882 fusion:872 cooccurence:774 experimental:817 database:900 textmining:907
Rv2153c murG UDP-N-acetylglucosamine--N-acetylmuramyl-(pentapeptide) pyrophosphoryl-undecaprenol-N-acetylglucosamine transferase 907 902 database:900
Rv2158c murE UDP-N-acetylmuramoylalanyl-D-glutamate--2,6-diaminopimelate ligase 922 853 experimental:817 textmining:494
Rv3711c dnaQ DNA polymerase III subunit epsilon 885 742 ctx neighborhood:739 textmining:574
Rv1391 dfp bifunctional phosphopantothenoylcysteine decarboxylase/phosphopantothenate--cysteine ligase 415 405 coexpression:405
Rv2208 cobS adenosylcobinamide-GDP ribazoletransferase 617 97 textmining:594
Rv2157c murF UDP-N-acetylmuramoyl-tripeptide--D-alanyl-D-alanine ligase 550 87 textmining:528
Rv0255c cobQ1 cobyric acid synthase 701 85 textmining:688
Rv0254c cobU bifunctional cobinamide kinase/cobinamide phosphate guanylyltransferase 679 77 textmining:667
Rv2065 cobH precorrin-8X methylmutase 807 63 textmining:803
Rv2677c hemY protoporphyrinogen oxidase 519 60 textmining:510
Rv2228c multifunctional RNASE H/alpha-ribazole phosphatase/acid phosphatase 658 54 textmining:654
Rv2152c murC UDP-N-acetylmuramate--alanine ligase 480 53 textmining:473
Rv3714c hyp hypothetical protein 810 51 textmining:809
Rv2392 cysH phosphoadenosine phosphosulfate reductase 514 50 textmining:510

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: cobyric acid synthase CobQ
  • MTBC0 PGAP product: type 1 glutamine amidotransferase
  • Pfam (hmmscan --cut_ga): GATase_3 PF07685.21 (E=3e-35)
  • (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_218230.1)
  • Domains: Pfam-A via hmmscan --cut_ga — GATase_3 (PF07685.21)
  • 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 COG3442
  • Curated reference: UniProt I6XI14 (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 — 19 functional partner(s); context anchor Rv3712
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003936|Rv3713|cobQ2
MVRIGLVLPDVMGTYGDGGNAVVLRQRLLLRGIAAEIVEITLADPVPDSLDLYTLGGAEDYAQRLATRHLRRYPGLQRAAGRGAPVLAICAAIQVLGHWYETSSGDRVDGVGLLDVTTSPQDARTIGELVSKPLLAGLTQPLTGFENHRGGTVLGPGTSPLGAVVKGAGNRAGDGFDGAVAGSVVATYMHGPCLARNPELADLLLSKVVGELAPLDLPEVDLLRRERLSAR