xerC Resolved · high auto-curated

H37Rv Rv2894c · MTBC0 mtbc0_003076 · 298 aa · 3224223–3225119 (-) · RefSeq NP_217410.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)tyrosine recombinase XerC
MTBC0 PGAP re-annotationtyrosine recombinase XerC
Revised (this work)Tyrosine recombinase XerC. Pfam: Phage_int_SAM_1 (PF02899.24), Phage_integrase (PF00589.28).

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

Curated reference (UniProt)

UniProt P9WF35 SwissProt · reviewed · Evidence at protein level
UniProt nameTyrosine recombinase XerC
Curated functionSite-specific tyrosine recombinase, which acts by catalyzing the cutting and rejoining of the recombining DNA molecules. The XerC-XerD complex is essential to convert dimers of the bacterial chromosome into monomers to permit their segregation at cell division. It also contributes to the segregational stability of plasmids (By similarity).

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category D Cell cycle control, cell division, chromosome partitioning
Preferred namexerC
eggNOG descriptionBelongs to the 'phage' integrase family. XerC subfamily
Orthologous groupCOG4974
KEGG orthology K03733, K04763
Gene Ontology (6) GO:0005575, GO:0005623, GO:0005886, GO:0016020, GO:0044464, GO:0071944

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 0.202 · purifying
Polymorphic sites (≥ 0.1% of strains) 6 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
Phage_int_SAM_1PF02899.24 2.7e-235–87 Phage integrase, N-terminal SAM-like domain
Phage_integrasePF00589.28 1.5e-50109–284 Phage integrase family

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

Closest characterised functional partner: Rv2646 (integrase), high confidence from genomic context alone (score 798 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv3242c hyp hypothetical protein 902 902 coexpression:902
Rv2584c apt adenine phosphoribosyltransferase 853 853 coexpression:853
Rv2646 integrase 798 798 ctx cooccurence:773
Rv2895c viuB mycobactin utilization protein ViuB 780 780 ctx neighborhood:779
Rv3754 tyrA prephenate dehydrogenase TyrA 774 774 coexpression:766
Rv1423 whiA transcriptional regulator WhiA 772 772 coexpression:767
Rv2153c murG UDP-N-acetylglucosamine--N-acetylmuramyl-(pentapeptide) pyrophosphoryl-undecaprenol-N-acetylglucosamine transferase 780 770 coexpression:731
Rv1435c hyp hypothetical protein 780 770 coexpression:770
Rv3226c hyp hypothetical protein 775 767 coexpression:767
Rv0063 oxidoreductase 746 746 coexpression:746
Rv2154c ftsW lipid II flippase FtsW 753 743 coexpression:735
Rv3717 hyp hypothetical protein 739 739 coexpression:731
Rv3209 hyp hypothetical protein 729 729 coexpression:729
Rv2896c dprA hyp hypothetical protein 672 652 ctx neighborhood:578
Rv3781 rfbE O-antigen/lipopolysaccharide ABC transporter ATP-binding protein RfbE 646 646 coexpression:646

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: tyrosine recombinase XerC
  • MTBC0 PGAP product: tyrosine recombinase XerC
  • Pfam (hmmscan --cut_ga): Phage_int_SAM_1 PF02899.24 (E=3e-23), Phage_integrase PF00589.28 (E=1e-50)
  • (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_217410.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Phage_int_SAM_1 (PF02899.24), Phage_integrase (PF00589.28)
  • 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 COG4974
  • Curated reference: UniProt P9WF35 (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 — 44 functional partner(s); context anchor Rv2646
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003076|Rv2894c|xerC
MQAILDEFDEYLALQCGRSVHTRRAYLGDLRSLFAFLADRGSSLDALTLSVLRSWLAATAGAGAARTTLARRTSAVKAFTAWAVRRGLLAGDPAARLQVPKARRTLPAVLRQDQALRAMAAAESGAEQGDPLALRDRLIVELLYATGIRVSELCGLDVDDIDTGHRLVRVLGKGNKQRTVPFGQPAADALHAWLVDGRRALVTAESGHALLLGARGRRLDVRQARTAVHQTVAAVDGAPDMGPHGLRHSAATHLLEGGADLRVVQELLGHSSLATTQLYTHVAVARLRAVHERAHPRA