bacA Family assigned · medium auto-curated

H37Rv Rv1819c · MTBC0 mtbc0_001933 · 639 aa · 2080897–2082816 (-) · RefSeq NP_216335.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)vitamin B12 transport ATP-binding protein BacA
MTBC0 PGAP re-annotationvitamin B12 ABC transporter ATP-binding protein BacA
Revised (this work)Vitamin B12 ABC transporter ATP-binding protein BacA. Pfam: ABC_membrane_2 (PF06472.21), SbmA_BacA (PF05992.18), ABC_tran (PF00005.34).

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

Curated reference (UniProt)

UniProt P9WQI9 SwissProt · reviewed · Evidence at protein level
UniProt nameHydrophilic compounds import ATP-binding/permease protein BacA
EC (curated) EC 7.6.2.-
Curated functionMulti-solute ABC transporter that mediates uptake of unrelated hydrophilic compounds. Can transport vitamin B12 and related corrinoids, and antimicrobial peptides such as bleomycin. Transmembrane domains (TMD) form a pore in the membrane and the ATP-binding domain (NBD) is responsible for energy generation. Contributes to maintenance of chronic infections.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
Preferred namebacA
eggNOG descriptionABC transporter
Orthologous groupCOG4178
KEGG orthology K02471
KEGG pathways map02010
Gene Ontology (28) GO:0005575, GO:0005576, GO:0005623, GO:0005886, GO:0005887, GO:0008150, GO:0009605, GO:0009607, GO:0016020, GO:0016021, GO:0031224, GO:0031226 +16 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 0.146 · strong purifying
Polymorphic sites (≥ 0.1% of strains) 7 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
ABC_membrane_2PF06472.21 3.6e-7954–358 ABC transporter transmembrane region 2
SbmA_BacAPF05992.18 5.1e-2567–398 SbmA/BacA-like family
ABC_tranPF00005.34 4.9e-16444–579 ABC transporter

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

Closest characterised functional partner: ilvG (acetolactate synthase large subunit IlvG), high confidence from genomic context alone (score 786 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv1820 ilvG acetolactate synthase large subunit IlvG 790 786 ctx neighborhood:785
Rv0435c ATPase 690 673 database:617
Rv1822 pgsA2 CDP-diacylglycerol--glycerol-3-phosphate 3-phosphatidyltransferase 653 653 ctx neighborhood:652
Rv1823 hyp hypothetical protein 651 652 ctx neighborhood:650
Rv1488 hyp hypothetical protein 633 625 database:581
Rv3090 hyp hypothetical protein 632 623 database:581
Rv3884c eccA2 ESX-2 secretion system protein EccA 641 621 database:617
Rv0654 carotenoid cleavage oxygenase 619 620 database:563
Rv3868 eccA1 ESX-1 secretion system protein EccA1 639 619 database:617
Rv0282 eccA3 ESX-3 secretion system protein EccA 638 618 database:617
Rv2737c recA recombinase A 616 615 experimental:608
Rv1825 hyp hypothetical protein 601 602 ctx neighborhood:599
Rv3293 pcd piperideine-6-carboxylic acid dehydrogenase 598 586 database:581
Rv0768 aldA aldehyde dehydrogenase AldA 598 586 database:581
Rv1731 gabD2 succinate-semialdehyde dehydrogenase 598 586 database:581

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: vitamin B12 transport ATP-binding protein BacA
  • MTBC0 PGAP product: vitamin B12 ABC transporter ATP-binding protein BacA
  • Pfam (hmmscan --cut_ga): ABC_membrane_2 PF06472.21 (E=4e-79), SbmA_BacA PF05992.18 (E=5e-25), ABC_tran PF00005.34 (E=5e-16)
  • (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_216335.1)
  • Domains: Pfam-A via hmmscan --cut_ga — ABC_membrane_2 (PF06472.21), SbmA_BacA (PF05992.18), ABC_tran (PF00005.34)
  • 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 COG4178
  • Curated reference: UniProt P9WQI9 (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 — 52 functional partner(s); context anchor ilvG
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_001933|Rv1819c|bacA
MGPKLFKPSIDWSRAFPDSVYWVGKAWTISAICVLAILVLLRYLTPWGRQFWRITRAYFVGPNSVRVWLMLGVLLLSVVLAVRLNVLFSYQGNDMYTALQKAFEGIASGDGTVKRSGVRGFWMSIGVFSVMAVLHVTRVMADIYLTQRFIIAWRVWLTHHLTQDWLDGRAYYRDLFIDETIDNPDQRIQQDVDIFTAGAGGTPNAPSNGTASTLLFGAVQSIISVISFTAILWNLSGTLNIFGVSIPRAMFWTVLVYVFVATVISFIIGRPLIWLSFRNEKLNAAFRYALVRLRDAAEAVGFYRGERVEGTQLQRRFTPVIDNYRRYVRRSIAFNGWNLSVSQTIVPLPWVIQAPRLFAGQIDFGDVGQTATSFGNIHDSLSFFRNNYDAFASFRAAIIRLHGLVDANEKGRALPAVLTRPSDDESVELNDIEVRTPAGDRLIDPLDVRLDRGGSLVITGRSGAGKTTLLRSLAELWPYASGTLHRPGGENETMFLSQLPYVPLGTLRDVVCYPNSAAAIPDATLRDTLTKVALAPLCDRLDEERDWAKVLSPGEQQRVAFARILLTKPKAVFLDESTSALDTGLEFALYQLLRSELPDCIVVSVSHRPALERLHENQLELLGGGQWRLAPVEAAPAEV