cstA Family assigned · medium auto-curated

H37Rv Rv3063 · MTBC0 mtbc0_003255 · 758 aa · 3448607–3450883 (+) · RefSeq NP_217579.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)carbon starvation protein A
MTBC0 PGAP re-annotationcarbon starvation CstA family protein
Revised (this work)Carbon starvation CstA family protein. Pfam: CstA (PF02554.21).

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

Curated reference (UniProt)

UniProt P9WP47 SwissProt · reviewed · Inferred from homology
UniProt namePeptide transporter CstA
Curated functionInvolved in peptide utilization.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category T Signal transduction mechanisms
Preferred namecstA
eggNOG descriptionCarbon starvation protein
Orthologous groupCOG1966
KEGG orthology K06200
Gene Ontology (23) GO:0005575, GO:0005623, GO:0005886, GO:0005887, GO:0007154, GO:0008150, GO:0009605, GO:0009987, GO:0009991, GO:0016020, GO:0016021, GO:0031224 +11 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 0.525 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 9 synonymous, 13 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
CstAPF02554.21 2.4e-24968–633 Carbon starvation protein CstA

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

Closest characterised functional partner: ligB (DNA ligase), high confidence from genomic context alone (score 758 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv3062 ligB DNA ligase 787 758 ctx neighborhood:756
Rv3667 acs acetyl-CoAsynthetase 695 683 coexpression:681
Rv2443 dctA C4-dicarboxylate-transport transmembrane protein DctA 585 559 coexpression:410
Rv1188 proline dehydrogenase 560 542 coexpression:542
Rv3061c fadE22 acyl-CoA dehydrogenase FadE22 485 485 ctx neighborhood:476
Rv1249c membrane protein 469 470 coexpression:460
Rv0887c hyp hypothetical protein 459 460 coexpression:453
Rv3293 pcd piperideine-6-carboxylic acid dehydrogenase 424 425 coexpression:425
Rv0409 ackA acetate kinase 421 421 coexpression:421
Rv0223c aldehyde dehydrogenase 419 420 coexpression:420
Rv2858c aldC aldehyde dehydrogenase AldC 419 420 coexpression:420
Rv0768 aldA aldehyde dehydrogenase AldA 419 420 coexpression:420
Rv1187 rocA pyrroline-5-carboxylate dehydrogenase RocA 419 420 coexpression:420
Rv1731 gabD2 succinate-semialdehyde dehydrogenase 418 418 coexpression:418
Rv0147 aldehyde dehydrogenase 417 418 coexpression:418

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: carbon starvation protein A
  • MTBC0 PGAP product: carbon starvation CstA family protein
  • Pfam (hmmscan --cut_ga): CstA PF02554.21 (E=2e-249)
  • (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_217579.1)
  • Domains: Pfam-A via hmmscan --cut_ga — CstA (PF02554.21)
  • 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 COG1966
  • Curated reference: UniProt P9WP47 (SwissProt, reviewed; Inferred from homology)
  • 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 — 26 functional partner(s); context anchor ligB
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003255|Rv3063|cstA
MAAPTPSNRIEERSGHASCVRADADLPPVAILGRSPITLRHKIFFVAVAVIGALAWTVVAFFRNEPVNAVWIVVAAGCTYIIGFRFYARLIEMKVVRPRDDHATPAEILDDGTDYVPTDRRVVFGHHFAAIAGAGPLVGPVLATQMGYLPSSIWIVVGAVLAGCVQDYLVLWISVRRRGRSLGQMVRDELGATAGVAALVGIPVIITIVIAVLALVVVRALAKSPWGVFSIAMTIPIAIFMGCYLRFLRPGRVSEVSLIGIGLLLLAVVSGDWVAHTSWGAAWFSLSPVTLCWLLISYGFAASVLPVWLLLAPRDYLSTFMKVGTIALLAIGVCAAHPIIEAPAVSKFAGSGNGPVFAGSLFPFLFITIACGALSGFHALICSGTTPKMLEKEGQMRVIGYGGMMTESFVAVIALLTAAILDQHLYFTLNAPSLHTHDSAATAAKYVNGLGLTGSPVTPDHISQAAASVGEQTIVSRTGGAPTLAFGMAEMLHRVVGGVGLKAFWYHFAIMFEALFILTTVDAGTRAARFMISDALGNFGGVLRKLQNPSWRPGAWACSLVVVAAWGSILLLGVTDPLGGINTLFPLFGIANQLLAGIALTVITVVVIKKGRLKWAWIPGIPLLWDLAVTLTASWQKIFSADPSVGYWTQHAHYAAAQHAGETAFGSATNADEINDVVRNTFVQGTLSIVFVVVVVLVVVAGVIVALKTIRGRGIPLAEDDPAPSTLFAPAGLIPTAAERKLQRRLGAPASASVAAPD