fbpA Resolved · high auto-curated

H37Rv Rv3804c · MTBC0 mtbc0_004032 · 338 aa · 4289752–4290768 (-) · RefSeq NP_218321.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)diacylglycerol acyltransferase/mycolyltransferase Ag85A
MTBC0 PGAP re-annotationdiacylglycerol acyltransferase/mycolyltransferase Ag85A
Revised (this work)Diacylglycerol acyltransferase/mycolyltransferase Ag85A. Pfam: Esterase (PF00756.27).

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

Curated reference (UniProt)

UniProt P9WQP3 SwissProt · reviewed · Evidence at protein level
UniProt nameDiacylglycerol acyltransferase/mycolyltransferase Ag85A
EC (curated) EC 2.3.1.122, EC 2.3.1.20
Curated functionThe antigen 85 proteins (FbpA, FbpB, FbpC) are responsible for the high affinity of mycobacteria for fibronectin, a large adhesive glycoprotein, which facilitates the attachment of M.tuberculosis to murine alveolar macrophages (AMs). They also help to maintain the integrity of the cell wall by catalyzing the transfer of mycolic acids to cell wall arabinogalactan, and through the synthesis of alpha,alpha-trehalose dimycolate (TDM, cord factor). They catalyze the transfer of a mycoloyl residue from one molecule of alpha,alpha-trehalose monomycolate (TMM) to another TMM, leading to the formation .

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
Preferred namecmtB
eggNOG descriptionfibronectin, a large adhesive glycoprotein, which facilitates the attachment of M.tuberculosis to murine alveolar macrophages (AMs). They also help to maintain the integrity of the cell wall by catalyzing the transfer of mycolic acids to cell wall arabinogalactan, and through the synthesis of alpha,alpha-trehalose dimycolate (TDM, cord factor). They catalyze the transfer of a mycoloyl residue from one molecule of alpha,alpha-trehalose monomycolate (TMM) to another TMM, leading to the formation of TDM
Orthologous groupCOG0627
EC number EC 2.3.1.122, EC 2.3.1.20
KEGG orthology K18851
KEGG pathways map00561, map01100
KEGG modules M00089
Gene Ontology (31) GO:0003674, GO:0003824, GO:0005488, GO:0005515, GO:0005575, GO:0005576, GO:0005618, GO:0005622, GO:0005623, GO:0005737, GO:0005886, GO:0008150 +19 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 0.524 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 5 synonymous, 8 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
EsterasePF00756.27 8.7e-7658–321 Putative esterase

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

Closest characterised functional partner: aftB (terminal beta-(1->2)-arabinofuranosyltransferase), high confidence from genomic context alone (score 864 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv0129c fbpC diacylglycerol acyltransferase/mycolyltransferase Ag85C 974 903 database:900 textmining:747
Rv1886c fbpB diacylglycerol acyltransferase/mycolyltransferase Ag85B 952 902 database:900 textmining:530
Rv3097c lipY triacylglycerol lipase Lip 904 901 database:900
Rv2252 dagK diacylglycerol kinase 900 900 database:900
Rv3805c aftB terminal beta-(1->2)-arabinofuranosyltransferase 864 864 ctx neighborhood:478 cooccurence:514 database:500
Rv1871c hyp hypothetical protein 848 843 coexpression:811
Rv3802c membrane protein 833 808 ctx cooccurence:702
Rv1872c lldD2 L-lactate dehydrogenase 805 805 coexpression:803
Rv0703 rplW 50S ribosomal protein L23 805 805 coexpression:805
Rv0685 tuf elongation factor Tu 777 778 coexpression:778
Rv0708 rplP 50S ribosomal protein L16 744 744 coexpression:744
Rv0702 rplD 50S ribosomal protein L4 741 741 coexpression:741
Rv1630 rpsA 30S ribosomal protein S1 734 734 coexpression:734
Rv0704 rplB 50S ribosomal protein L2 733 733 coexpression:733
Rv0705 rpsS 30S ribosomal protein S19 732 732 coexpression:732

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: diacylglycerol acyltransferase/mycolyltransferase Ag85A
  • MTBC0 PGAP product: diacylglycerol acyltransferase/mycolyltransferase Ag85A
  • Pfam (hmmscan --cut_ga): Esterase PF00756.27 (E=9e-76)
  • (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_218321.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Esterase (PF00756.27)
  • 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 COG0627
  • Curated reference: UniProt P9WQP3 (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 — 86 functional partner(s); context anchor aftB
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_004032|Rv3804c|fbpA
MQLVDRVRGAVTGMSRRLVVGAVGAALVSGLVGAVGGTATAGAFSRPGLPVEYLQVPSPSMGRDIKVQFQSGGANSPALYLLDGLRAQDDFSGWDINTPAFEWYDQSGLSVVMPVGGQSSFYSDWYQPACGKAGCQTYKWETFLTSELPGWLQANRHVKPTGSAVVGLSMAASSALTLAIYHPQQFVYAGAMSGLLDPSQAMGPTLIGLAMGDAGGYKASDMWGPKEDPAWQRNDPLLNVGKLIANNTRVWVYCGNGKPSDLGGNNLPAKFLEGFVRTSNIKFQDAYNAGGGHNGVFDFPDSGTHSWEYWGAQLNAMKPDLQRALGATPNTGPAPQGA