xthA Resolved · high auto-curated

H37Rv Rv0427c · MTBC0 - · 291 aa · 516017–516892 (-) · RefSeq NP_214941.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)exodeoxyribonuclease III protein XthA
MTBC0 PGAP re-annotation
Revised (this work)Exodeoxyribonuclease III protein XthA. Pfam: Exo_endo_phos (PF03372.30).

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

Annotated on the H37Rv protein: this gene has no 1:1 ancestral MTBC0 anchor (PE/PPE, paralogue, IS element, or otherwise unanchored CDS).

Curated reference (UniProt)

UniProt P96273 TrEMBL · unreviewed · Evidence at protein level
UniProt nameProbable exodeoxyribonuclease III protein XthA

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category L Replication, recombination and repair
Preferred namexthA
eggNOG descriptionexodeoxyribonuclease III
Orthologous groupCOG0708
EC number EC 3.1.11.2
KEGG orthology K01142
KEGG pathways map03410

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 0.649 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 1 synonymous, 2 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
Exo_endo_phosPF03372.30 1.8e-3027–281 Endonuclease/Exonuclease/phosphatase family

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

Closest characterised functional partner: def (polypeptide deformylase), high confidence from genomic context alone (score 894 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv0429c def polypeptide deformylase 952 894 ctx neighborhood:881 textmining:566
Rv0428c GCN5-like N-acetyltransferase 946 883 ctx neighborhood:881 textmining:562
Rv3589 mutY A/G-specific adenine glycosylase 903 865 experimental:428 database:771
Rv2116 lppK lipoprotein LppK 850 834 experimental:414 database:653
Rv0002 dnaN DNA polymerase III subunit beta 850 834 experimental:414 database:653
Rv0670 end endonuclease IV 951 826 experimental:825 textmining:732
Rv1711 RNA pseudouridine synthase 814 815 coexpression:805
Rv2976c ung uracil-DNA glycosylase 852 807 database:743
Rv3674c nth endonuclease III 823 799 experimental:403 database:641
Rv1870c hyp hypothetical protein 818 799 experimental:403 database:641
Rv1156 hyp hypothetical protein 818 799 experimental:403 database:641
Rv1629 polA DNA polymerase I 932 781 database:662 textmining:703
Rv1317c alkA bifunctional regulatory protein/DNA repair enzyme AlkA 894 759 database:651 textmining:579
Rv2090 5'-3' exonuclease 778 748 database:662
Rv0938 ligD multifunctional non-homologous end joining DNA repair protein/ATP dependent DNA ligase LigD 763 738 database:644

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

  • Annotation from H37Rv (no MTBC0 1:1 anchor; H37Rv protein used): exodeoxyribonuclease III protein XthA
  • Pfam (hmmscan --cut_ga): Exo_endo_phos PF03372.30 (E=2e-30)
  • (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_214941.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Exo_endo_phos (PF03372.30)
  • 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 COG0708
  • Curated reference: UniProt P96273 (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 def
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>H37Rv|Rv0427c|xthA
MPDGTIDGGHPQRPASPRLRSPLLRLATWNVNSIRTRLDRVLDWLGRADVDVLAMQETKCPDGQFPALPLFELGYDVAHVGFDQWNGVAIASRVGLDDVRVGFDGQPSWSGKPEVAATTEARALGATCGGIRVWSLYVPNGRALDDPHYTYKLDWLAALRDTAEGWLRDDPAAPIALMGDWNIAPTDDDVWSTEFFAGCTHVSEPERKAFNAIVDAQFTDVVRPFTPGPGVYTYWDYTQLRFPKKQGMRIDFILGSPALAARVMDAQIVREERKGKAPSDHAPVLVDLHAG