alaS Resolved · high auto-curated

H37Rv Rv2555c · MTBC0 mtbc0_002723 · 904 aa · 2897316–2900030 (-) · RefSeq NP_217071.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)alanine--tRNA ligase
MTBC0 PGAP re-annotationalanine--tRNA ligase
Revised (this work)Alanine--tRNA ligase. Pfam: tRNA-synt_2c (PF01411.25), tRNA_SAD (PF07973.20), DHHA1 (PF02272.25).

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

Curated reference (UniProt)

UniProt P9WFW7 SwissProt · reviewed · Evidence at protein level
UniProt nameAlanine--tRNA ligase
EC (curated) EC 6.1.1.7
Curated functionCatalyzes the attachment of alanine to tRNA(Ala) in a two-step reaction: alanine is first activated by ATP to form Ala-AMP and then transferred to the acceptor end of tRNA(Ala). Also edits incorrectly charged Ser-tRNA(Ala) and Gly-tRNA(Ala) via its editing domain.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category J Translation, ribosomal structure and biogenesis
Preferred namealaS
eggNOG descriptionCatalyzes the attachment of alanine to tRNA(Ala) in a two-step reaction alanine is first activated by ATP to form Ala- AMP and then transferred to the acceptor end of tRNA(Ala). Also edits incorrectly charged Ser-tRNA(Ala) and Gly-tRNA(Ala) via its editing domain
Orthologous groupCOG0013
EC number EC 6.1.1.7
KEGG orthology K01872
KEGG pathways map00970
KEGG modules M00359, M00360
Gene Ontology (78) GO:0003674, GO:0003824, GO:0004812, GO:0004813, GO:0005488, GO:0005575, GO:0005618, GO:0005622, GO:0005623, GO:0005737, GO:0005829, GO:0005886 +66 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 0.256 · purifying
Polymorphic sites (≥ 0.1% of strains) 4 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
tRNA-synt_2cPF01411.25 2.2e-1985–574 tRNA synthetases class II (A)
tRNA_SADPF07973.20 2.6e-16673–717 Threonyl and Alanyl tRNA synthetase second additional domain
DHHA1PF02272.25 1.7e-13792–897 DHHA1 domain

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

Closest characterised functional partner: ruvX (Holliday junction resolvase), high confidence from genomic context alone (score 981 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv2554c ruvX Holliday junction resolvase 993 981 ctx neighborhood:881 coexpression:826 textmining:652
Rv2553c mltG membrane protein 939 940 ctx neighborhood:881 coexpression:514
Rv1691 hyp hypothetical protein 925 920 experimental:775 database:644
Rv3529c hyp hypothetical protein 925 920 experimental:775 database:644
Rv2267c stf3 hyp hypothetical protein 925 919 experimental:775 database:644
Rv2552c aroE shikimate 5-dehydrogenase 888 888 ctx neighborhood:881
Rv1650 pheT phenylalanine--tRNA ligase subunit beta 969 852 coexpression:703 textmining:800
Rv3812 PE_PGRS62 PE-PGRS family protein PE_PGRS62 848 836 experimental:570 database:622
Rv2328 PE23 PE family protein PE23 848 836 experimental:570 database:622
Rv3036c TB22.2 hyp hypothetical protein 848 836 experimental:570 database:622
Rv0832 PE_PGRS12 PE-PGRS family protein PE_PGRS12 848 836 experimental:570 database:622
Rv2614c thrS threonine--tRNA ligase 857 813 ctx cooccurence:436 coexpression:636
Rv2551c hyp hypothetical protein 797 797 ctx neighborhood:791
Rv2572c aspS aspartate--tRNA ligase 829 792 coexpression:684
Rv2556c hyp hypothetical protein 789 789 ctx neighborhood:779

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: alanine--tRNA ligase
  • MTBC0 PGAP product: alanine--tRNA ligase
  • Pfam (hmmscan --cut_ga): tRNA-synt_2c PF01411.25 (E=2e-198), tRNA_SAD PF07973.20 (E=3e-16), DHHA1 PF02272.25 (E=2e-13)
  • (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_217071.1)
  • Domains: Pfam-A via hmmscan --cut_ga — tRNA-synt_2c (PF01411.25), tRNA_SAD (PF07973.20), DHHA1 (PF02272.25)
  • 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 COG0013
  • Curated reference: UniProt P9WFW7 (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 — 150 functional partner(s); context anchor ruvX
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_002723|Rv2555c|alaS
MQTHEIRKRFLDHFVKAGHTEVPSASVILDDPNLLFVNAGMVQFVPFFLGQRTPPYPTATSIQKCIRTPDIDEVGITTRHNTFFQMAGNFSFGDYFKRGAIELAWALLTNSLAAGGYGLDPERIWTTVYFDDDEAVRLWQEVAGLPAERIQRRGMADNYWSMGIPGPCGPSSEIYYDRGPEFGPAGGPIVSEDRYLEVWNLVFMQNERGEGTTKEDYQILGPLPRKNIDTGMGVERIALVLQDVHNVYETDLLRPVIDTVARVAARAYDVGNHEDDVRYRIIADHSRTAAILIGDGVSPGNDGRGYVLRRLLRRVIRSAKLLGIDAAIVGDLMATVRNAMGPSYPELVADFERISRIAVAEETAFNRTLASGSRLFEEVASSTKKSGATVLSGSDAFTLHDTYGFPIELTLEMAAETGLQVDEIGFRELMAEQRRRAKADAAARKHAHADLSAYRELVDAGATEFTGFDELRSQARILGIFVDGKRVPVVAHGVAGGAGEGQRVELVLDRTPLYAESGGQIADEGTISGTGSSEAARAAVTDVQKIAKTLWVHRVNVESGEFVEGDTVIAAVDPGWRRGATQGHSGTHMVHAALRQVLGPNAVQAGSLNRPGYLRFDFNWQGPLTDDQRTQVEEVTNEAVQADFEVRTFTEQLDKAKAMGAIALFGESYPDEVRVVEMGGPFSLELCGGTHVSNTAQIGPVTILGESSIGSGVRRVEAYVGLDSFRHLAKERALMAGLASSLKVPSEEVPARVANLVERLRAAEKELERVRMASARAAATNAAAGAQRIGNVRLVAQRMSGGMTAADLRSLIGDIRGKLGSEPAVVALIAEGESQTVPYAVAANPAAQDLGIRANDLVKQLAVAVEGRGGGKADLAQGSGKNPTGIDAALDAVRSEIAVIARVG