accA2 Family assigned · medium auto-curated

H37Rv Rv0973c · MTBC0 mtbc0_001039 · 667 aa · 1090962–1092965 (-) · RefSeq NP_215488.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)acetyl/propionyl-CoA carboxylase subuit alpha
MTBC0 PGAP re-annotationbiotin carboxylase N-terminal domain-containing protein
Revised (this work)Biotin carboxylase N-terminal domain-containing protein. Pfam: Biotin_carb_N (PF00289.29), CPSase_L_D2 (PF02786.23), Dala_Dala_lig_C (PF07478.19), Biotin_carb_C (PF02785.26), BT_MCC_alpha (PF21139.4), Biotin_lipoyl (PF00364.29).

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

Curated reference (UniProt)

UniProt P71538 TrEMBL · unreviewed · Evidence at protein level
UniProt nameBiotin-dependent 3-methylcrotonyl-coenzyme A carboxylase alpha1 subunit
EC (curated) EC 6.3.4.14
Curated functionComponent of a biotin-dependent acyl-CoA carboxylase complex. This subunit catalyzes the ATP-dependent carboxylation of the biotin carried by the biotin carboxyl carrier (BCC) domain, resulting in the formation of carboxyl biotin. When associated with the beta1 subunit AccD1, is involved in branched amino-acid catabolism with methylcrotonyl coenzyme A as the substrate.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category I Lipid transport and metabolism
Preferred nameaccA2
eggNOG descriptioncarboxylase
Orthologous groupCOG4770
EC number EC 6.4.1.1, EC 6.4.1.3, EC 6.4.1.4
KEGG orthology K01959, K01965, K01968
KEGG pathways map00020, map00280, map00620, map00630, map00640, map00720, map01100, map01120, map01130, map01200, map01230
KEGG modules M00036, M00173, M00373, M00620, M00741

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 0.79 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 5 synonymous, 11 missense, 0 nonsense, 1 frameshift
Disruption 1 distinct premature-stop/frameshift site(s); most common in 0.25% of strains (360) · clonal

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
Biotin_carb_NPF00289.29 8.6e-403–107 Biotin carboxylase, N-terminal domain
CPSase_L_D2PF02786.23 3.2e-56133–317 Carbamoyl-phosphate synthase L chain, ATP binding domain
Dala_Dala_lig_CPF07478.19 9.6e-07136–286 D-ala D-ala ligase C-terminus
Biotin_carb_CPF02785.26 7.5e-26329–445 Biotin carboxylase C-terminal domain
BT_MCC_alphaPF21139.4 2.1e-10466–571 Methylcrotonyl-CoA carboxylase, alpha-subunit, BT domain
Biotin_lipoylPF00364.29 5.8e-18590–653 Biotin-requiring enzyme

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

Closest characterised functional partner: accD2 (acetyl-/propionyl-CoA carboxylase subunit beta), high confidence from genomic context alone (score 1000 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv0974c accD2 acetyl-/propionyl-CoA carboxylase subunit beta 999 1000 ctx neighborhood:881 coexpression:918 experimental:454 database:956 textmining:898
Rv0904c accD3 acetyl-CoAcarboxylase carboxyl transferase subunit beta 998 993 coexpression:486 experimental:975 textmining:759
Rv2247 accD6 acetyl-/propionyl-CoA carboxylase subunit beta 995 988 coexpression:435 experimental:454 database:956 textmining:634
Rv3280 accD5 propionyl-CoA carboxylase subunit beta 995 987 coexpression:435 experimental:454 database:956 textmining:693
Rv0972c fadE12 acyl-CoA dehydrogenase fadE12 993 986 ctx neighborhood:882 coexpression:874 textmining:584
Rv0975c fadE13 acyl-CoA dehydrogenase FadE13 984 984 ctx neighborhood:882 coexpression:856
Rv0976c hyp hypothetical protein 984 983 ctx neighborhood:881 coexpression:832
Rv0971c echA7 enoyl-CoA hydratase EchA7 967 930 ctx neighborhood:882 textmining:555
Rv2790c ltp1 lipid-transfer protein 928 925 database:900
Rv3667 acs acetyl-CoAsynthetase 925 918 database:900
Rv3285 accA3 bifunctional protein acetyl-/propionyl-CoA carboxylase subunit alpha AccA 942 916 database:900
Rv2501c accA1 acetyl/propionyl-CoA carboxylase subuit alpha 924 913 database:900
Rv0408 pta phosphate acetyltransferase 917 905 database:900
Rv1322A hyp hypothetical protein 909 905 database:900
Rv0753c mmsA methylmalonate-semialdehyde dehydrogenase 906 902 database:900

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: acetyl/propionyl-CoA carboxylase subuit alpha
  • MTBC0 PGAP product: biotin carboxylase N-terminal domain-containing protein
  • Pfam (hmmscan --cut_ga): Biotin_carb_N PF00289.29 (E=9e-40), CPSase_L_D2 PF02786.23 (E=3e-56), Dala_Dala_lig_C PF07478.19 (E=1e-06), Biotin_carb_C PF02785.26 (E=7e-26), BT_MCC_alpha PF21139.4 (E=2e-10), Biotin_lipoyl PF00364.29 (E=6e-18)
  • (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_215488.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Biotin_carb_N (PF00289.29), CPSase_L_D2 (PF02786.23), Dala_Dala_lig_C (PF07478.19), Biotin_carb_C (PF02785.26), BT_MCC_alpha (PF21139.4), Biotin_lipoyl (PF00364.29)
  • 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 COG4770
  • Curated reference: UniProt P71538 (TrEMBL, unreviewed; 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 — 71 functional partner(s); context anchor accD2
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_001039|Rv0973c|accA2
MGITRVLVANRGEIARRVFATCRRLGLGTVAVYTDPDAAAPHVAEADARVRLPQTTDYLNAEAIIAAAQAAGADAVHPGYGFLSENAEFAAAVQEAGLTWVGPPVDAVRAMGSKIESKKLMAAAGVPVLEELDPDAVTTAQLPVLVKASAGGGGRGMRVVHELSALPAEVEAARREAQSAFGDPTVFCERYLPTGHHVEVQVMADTHGTVWAVGERECSIQRRHQKIIEEAPSPLVERVPGMRAKLFDAARLAASAIGYTGAGTVEFLADDSPGREGEFYFLEMNTRLQVEHPVTEETTGLDLVELQLMIADCGRLDTEPPPAQGYSIEARLYAEDPAHGWQPQAGVMHTIEVPGVRAQFDSLGQRTGIRLDSGIVDGSTVSIHYDPMLAKVVSYGATRRQAALVLADALVRARLHGLRTNRELLVNVLRHPAFLDGATDTGFFDTHGMAELSTPLADTATLRLSAIAAALADAEHNRASAGVFSSIPSGWRNLASGYQVKTYRDDADTEHRVEYRFTRTGLALPGDPVVQLVSADVDQVVLAQDGVAHGFTVARHGPDVYVDSARGPVHLVALSRFPEPSSAVEQGSLVAPMPGNVIRIGAEVGDTVTAGQPLIWLEAMKMEHTIAAPADGVLTHVSVNTGQQVEVGAILARVEAPQNGPAEGDSP