fadD6 Resolved · high auto-curated

H37Rv Rv1206 · MTBC0 mtbc0_001294 · 597 aa · 1357774–1359567 (+) · RefSeq NP_215722.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)fatty-acid--CoA ligase FadD6
MTBC0 PGAP re-annotationlong-chain-acyl-CoA synthetase FadD6
Revised (this work)Long-chain-acyl-CoA synthetase FadD6. Pfam: AMP-binding (PF00501.35), AMP-binding_C (PF13193.13).

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

Curated reference (UniProt)

UniProt O05307 SwissProt · reviewed · Evidence at protein level
UniProt nameMedium/long-chain-fatty-acid--CoA ligase FadD6
EC (curated) EC 6.2.1.2, EC 6.2.1.3
Curated functionCatalyzes the activation of medium/long-chain fatty acids as acyl-coenzyme A (acyl-CoA). May play a role in the uptake of fatty acids by trapping them metabolically as CoA esters. May also play an important role in the channeling of fatty acids into triacylglycerol (TAG) for use by Mycobacterium during its dormancy.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category I Lipid transport and metabolism
Q Secondary metabolites biosynthesis, transport and catabolism
Preferred namefadD6
eggNOG descriptionActivates fatty acids by binding to coenzyme A
Orthologous groupCOG0318
KEGG orthology K00666

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 0.528 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 2 synonymous, 3 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
AMP-bindingPF00501.35 1.3e-5853–405 AMP-binding enzyme
AMP-binding_CPF13193.13 9.8e-10473–549 AMP-binding enzyme C-terminal domain

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

Closest characterised functional partner: gpgS (glucosyl-3-phosphoglycerate synthase), high confidence from genomic context alone (score 818 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv1205 log hyp hypothetical protein 853 853 ctx neighborhood:811
Rv1208 gpgS glucosyl-3-phosphoglycerate synthase 818 818 ctx neighborhood:796
Rv1207 folP2 dihydropteroate synthase 798 798 ctx neighborhood:796
Rv1210 tagA DNA-3-methyladenine glycosylase I TagA 756 756 ctx neighborhood:756
Rv1209 hyp hypothetical protein 728 728 ctx neighborhood:728
Rv0719 rplF 50S ribosomal protein L6 696 696 experimental:402 database:510
Rv3825c pks2 phthioceranic/hydroxyphthioceranic acid synthase 707 682
Rv2940c mas multifunctional mycocerosic acid synthase 709 681
Rv2048c pks12 polyketide synthase 706 680
Rv2933 ppsC phthiocerol synthesis polyketide synthase type I PpsC 705 680
Rv1527c pks5 polyketide synthase 705 680
Rv3800c pks13 polyketide synthase 706 638
Rv2946c pks1 polyketide synthase 664 632
Rv1661 pks7 polyketide synthase 633 612
Rv1181 pks4 polyketide beta-ketoacyl synthase 633 612

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: fatty-acid--CoA ligase FadD6
  • MTBC0 PGAP product: long-chain-acyl-CoA synthetase FadD6
  • Pfam (hmmscan --cut_ga): AMP-binding PF00501.35 (E=1e-58), AMP-binding_C PF13193.13 (E=1e-09)
  • (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_215722.1)
  • Domains: Pfam-A via hmmscan --cut_ga — AMP-binding (PF00501.35), AMP-binding_C (PF13193.13)
  • 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 COG0318
  • Curated reference: UniProt O05307 (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 — 81 functional partner(s); context anchor gpgS
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_001294|Rv1206|fadD6
MSDYYGGAHTTVRLIDLATRMPRVLADTPVIVRGAMTGLLARPNSKASIGTVFQDRAARYGDRVFLKFGDQQLTYRDANATANRYAAVLAARGVGPGDVVGIMLRNSPSTVLAMLATVKCGAIAGMLNYHQRGEVLAHSLGLLDAKVLIAESDLVSAVAECGASRGRVAGDVLTVEDVERFATTAPATNPASASAVQAKDTAFYIFTSGTTGFPKASVMTHHRWLRALAVFGGMGLRLKGSDTLYSCLPLYHNNALTVAVSSVINSGATLALGKSFSASRFWDEVIANRATAFVYIGEICRYLLNQPAKPTDRAHQVRVICGNGLRPEIWDEFTTRFGVARVCEFYAASEGNSAFINIFNVPRTAGVSPMPLAFVEYDLDTGDPLRDASGRVRRVPDGEPGLLLSRVNRLQPFDGYTDPVASEKKLVRNAFRDGDCWFNTGDVMSPQGMGHAAFVDRLGDTFRWKGENVATTQVEAALASDQTVEECTVYGVQIPRTGGRAGMAAITLRAGAEFDGQALARTVYGHLPGYALPLFVRVVGSLAHTTTFKSRKVELRNQAYGADIEDPLYVLAGPDEGYVPYYAEYPEEVSLGRRPQG