glfT1 Resolved · high auto-curated

H37Rv Rv3782 · MTBC0 - · 304 aa · 4228347–4229261 (+) · RefSeq YP_178014.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)galactofuranosyl transferase GlfT
MTBC0 PGAP re-annotation
Revised (this work)Galactofuranosyl transferase GlfT. Pfam: Glycos_transf_2 (PF00535.33).

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

Annotated on the H37Rv protein: this gene has no 1:1 ancestral MTBC0 anchor (PE/PPE, paralogue, IS element, or otherwise unanchored CDS).

Curated reference (UniProt)

UniProt P9WMX3 SwissProt · reviewed · Evidence at protein level
UniProt nameGalactofuranosyltransferase GlfT1
EC (curated) EC 2.4.1.287
Curated functionInvolved in the biosynthesis of the arabinogalactan (AG) region of the mycolylarabinogalactan-peptidoglycan (mAGP) complex, an essential component of the mycobacterial cell wall. Catalyzes the transfer of the first two galactofuranosyl (Galf) units from UDP-galactofuranose (UDP-Galf) onto the rhamnosyl-GlcNAc-diphospho-decaprenol (Rha-GlcNAc-PP-C50) acceptor, yielding galactofuranosyl-galactofuranosyl-rhamnosyl-GlcNAc-diphospho-decaprenol (Galf-Galf-Rha-GlcNAc-PP-C50). Thus, GlfT1 is the initiator of galactan synthesis, while GlfT2 continues with the subsequent polymerization events.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
Preferred nameglfT1
eggNOG descriptionPFAM Glycosyl transferase family 2
Orthologous groupCOG1216
EC number EC 2.4.1.287
KEGG orthology K16649
CAZy family GT2
Gene Ontology (35) GO:0003674, GO:0003824, GO:0005575, GO:0005623, GO:0005886, GO:0008150, GO:0008152, GO:0008378, GO:0009058, GO:0009059, GO:0009987, GO:0016020 +23 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 0.356 · 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
Glycos_transf_2PF00535.33 4.6e-078–116 Glycosyl transferase family 2

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

Closest characterised functional partner: rfbD (O-antigen/lipopolysaccharide ABC transporter permease RfbD), high confidence from genomic context alone (score 994 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv3783 rfbD O-antigen/lipopolysaccharide ABC transporter permease RfbD 998 994 ctx neighborhood:881 cooccurence:640 coexpression:876 textmining:815
Rv3808c glfT2 galactofuranosyl transferase GlfT 998 980 ctx cooccurence:770 database:900 textmining:934
Rv3781 rfbE O-antigen/lipopolysaccharide ABC transporter ATP-binding protein RfbE 992 939 ctx neighborhood:882 textmining:879
Rv3265c wbbL1 N-acetylglucosaminyl-diphospho-decaprenol L-rhamnosyltransferase 962 920 database:900 textmining:550
Rv3809c glf UDP-galactopyranose mutase 962 901 ctx cooccurence:744 database:500 textmining:637
Rv3780 bpa hyp hypothetical protein 943 884 ctx neighborhood:882 textmining:533
Rv3779 transmembrane protein 908 881 ctx neighborhood:881
Rv3311 hyp hypothetical protein 733 733 ctx cooccurence:731
Rv3212 hyp hypothetical protein 700 701 ctx cooccurence:683
Rv3839 hyp hypothetical protein 665 666 ctx cooccurence:664
Rv3778c aminotransferase 638 638 ctx neighborhood:636
Rv3004 cfp6 low molecular weight protein antigen 6 598 598 ctx cooccurence:597
Rv3438 hyp hypothetical protein 578 578 ctx cooccurence:577
Rv2744c 35kd_ag hyp hypothetical protein 573 574 ctx cooccurence:571
Rv1083 hyp hypothetical protein 548 548 ctx cooccurence:548

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

  • Annotation from H37Rv (no MTBC0 1:1 anchor; H37Rv protein used): galactofuranosyl transferase GlfT
  • Pfam (hmmscan --cut_ga): Glycos_transf_2 PF00535.33 (E=5e-07)
  • (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 YP_178014.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Glycos_transf_2 (PF00535.33)
  • 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 COG1216
  • Curated reference: UniProt P9WMX3 (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 — 56 functional partner(s); context anchor rfbD
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>H37Rv|Rv3782|glfT1
MTESVFAVVVTHRRPDELAKSLDVLTAQTRLPDHLIVVDNDGCGDSPVRELVAGQPIATTYLGSRRNLGGAGGFALGMLHALAQGADWVWLADDDGHAQDARVLATLLACAEKYSLAEVSPMVCNIDDPTRLAFPLRRGLVWRRRASELRTEAGQELLPGIASLFNGALFRASTLAAIGVPDLRLFIRGDEVEMHRRLIRSGLPFGTCLDAAYLHPCGSDEFKPILCGRMHAQYPDDPGKRFFTYRNRGYVLSQPGLRKLLAQEWLRFGWFFLVTRRDPKGLWEWIRLRRLGRREKFGKPGGSA