embC Resolved · high auto-curated

H37Rv Rv3793 · MTBC0 mtbc0_004021 · 1094 aa · 4263984–4267268 (+) · RefSeq NP_218310.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)arabinosyltransferase C
MTBC0 PGAP re-annotationarabinosyltransferase EmbC
Revised (this work)Arabinosyltransferase EmbC. Pfam: Arabino_trans_N (PF17689.9), Arabinose_trans (PF04602.19), Arabino_trans_C (PF14896.13).

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

Curated reference (UniProt)

UniProt P9WNL5 SwissProt · reviewed · Evidence at protein level
UniProt nameProbable arabinosyltransferase C
EC (curated) EC 2.4.2.-
Curated functionArabinosyl transferase responsible for the polymerization of arabinose into the arabinan of arabinogalactan.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category M Cell wall / membrane / envelope biogenesis
Preferred nameembC
eggNOG descriptionCell wall arabinan synthesis protein
Orthologous groupCOG1807
KEGG orthology K11386, K11387
Gene Ontology (34) GO:0003674, GO:0003824, GO:0005575, GO:0005622, GO:0005623, GO:0005737, GO:0005829, GO:0006629, GO:0006643, GO:0006664, GO:0008150, GO:0008152 +22 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 0.483 · purifying
Polymorphic sites (≥ 0.1% of strains) 10 synonymous, 13 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
Arabino_trans_NPF17689.9 3.4e-4753–221 Arabinosyltransferase concanavalin like domain
Arabinose_transPF04602.19 1.5e-205225–681 Mycobacterial cell wall arabinan synthesis protein
Arabino_trans_CPF14896.13 2.5e-151720–1092 EmbC C-terminal domain

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

Closest characterised functional partner: aftA (arabinofuranosyltransferase), high confidence from genomic context alone (score 983 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv2244 acpM meromycolate extension acyl carrier protein 997 997 experimental:997
Rv3792 aftA arabinofuranosyltransferase 998 983 ctx neighborhood:881 cooccurence:754 coexpression:474 textmining:922
Rv3789 GtrA family protein 964 949 ctx neighborhood:823 cooccurence:720
Rv3790 dprE1 decaprenylphosphoryl-beta-D-ribose oxidase 972 941 ctx neighborhood:881 cooccurence:486 textmining:542
Rv3791 dprE2 decaprenylphosphoryl-D-2-keto erythropentose reductase 961 937 ctx neighborhood:881 cooccurence:485 textmining:405
Rv3794 embA arabinosyltransferase A 867 848 ctx neighborhood:780
Rv3802c membrane protein 805 805 ctx cooccurence:771
Rv3805c aftB terminal beta-(1->2)-arabinofuranosyltransferase 968 768 ctx cooccurence:756 textmining:870
Rv2673 aftC alpha-(1->3)-arabinofuranosyltransferase 919 764 ctx cooccurence:760 textmining:672
Rv3438 hyp hypothetical protein 745 746 ctx cooccurence:738
Rv3244c lpqB lipoprotein LpqB 744 744 ctx cooccurence:741
Rv1476 membrane protein 740 740 ctx cooccurence:737
Rv3788 hyp hypothetical protein 736 736 ctx neighborhood:732
Rv0996 transmembrane protein 735 736 ctx cooccurence:734
Rv3850 hyp hypothetical protein 733 734 ctx cooccurence:730

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: arabinosyltransferase C
  • MTBC0 PGAP product: arabinosyltransferase EmbC
  • Pfam (hmmscan --cut_ga): Arabino_trans_N PF17689.9 (E=3e-47), Arabinose_trans PF04602.19 (E=2e-205), Arabino_trans_C PF14896.13 (E=3e-151)
  • (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_218310.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Arabino_trans_N (PF17689.9), Arabinose_trans (PF04602.19), Arabino_trans_C (PF14896.13)
  • 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 COG1807
  • Curated reference: UniProt P9WNL5 (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 — 121 functional partner(s); context anchor aftA
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_004021|Rv3793|embC
MATEAAPPRIAVRLPSTSVRDAGANYRIARYVAVVAGLLGAVLAIATPLLPVNQTTAQLNWPQNGTFASVEAPLIGYVATDLNITVPCQAAAGLAGSQNTGKTVLLSTVPKQAPKAVDRGLLLQRANDDLVLVVRNVPLVTAPLSQVLGPTCQRLTFTAHADRVAAEFVGLVQGPNAEHPGAPLRGERSGYDFRPQIVGVFTDLAGPAPPGLSFSASVDTRYSSSPTPLKMAAMILGVALTGAALVALHILDTADGMRHRRFLPARWWSIGGLDTLVIAVLVWWHFVGANTSDDGYILTMARVSEHAGYMANYYRWFGTPEAPFGWYYDLLALWAHVSTASIWMRLPTLAMALTCWWVISREVIPRLGHAVKTSRAAAWTAAGMFLAVWLPLDNGLRPEPIIALGILLTWCSVERAVATSRLLPVAIACIIGALTLFSGPTGIASIGALLVAIGPLRTILHRRSRRFGVLPLVAPILAAATVTAIPIFRDQTFAGEIQANLLKRAVGPSLKWFDEHIRYERLFMASPDGSIARRFAVLALVLALAVSVAMSLRKGRIPGTAAGPSRRIIGITIISFLAMMFTPTKWTHHFGVFAGLAGSLGALAAVAVTGAAMRSRRNRTVFAAVVVFVLALSFASVNGWWYVSNFGVPWSNSFPKWRWSLTTALLELTVLVLLLAAWFHFVANGDGRRTARPTRFRARLAGIVQSPLAIATWLLVLFEVVSLTQAMISQYPAWSVGRSNLQALAGKTCGLAEDVLVELDPNAGMLAPVTAPLADALGAGLSEAFTPNGIPADVTADPVMERPGDRSFLNDDGLITGSEPGTEGGTTAAPGINGSRARLPYNLDPARTPVLGSWRAGVQVPAMLRSGWYRLPTNEQRDRAPLLVVTAAGRFDSREVRLQWATDEQAAAGHHGGSMEFADVGAAPAWRNLRAPLSAIPSTATQVRLVADDQDLAPQHWIALTPPRIPRVRTLQNVVGAADPVFLDWLVGLAFPCQRPFGHQYGVDETPKWRILPDRFGAEANSPVMDHNGGGPLGITELLMRATTVASYLKDDWFRDWGALQRLTPYYPDAQPADLNLGTVTRSGLWSPAPLRRG