xerD Resolved · high auto-curated

H37Rv Rv1701 · MTBC0 mtbc0_001809 · 311 aa · 1938217–1939152 (+) · RefSeq NP_216217.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)tyrosine recombinase XerD
MTBC0 PGAP re-annotationsite-specific tyrosine recombinase XerD
Revised (this work)Site-specific tyrosine recombinase XerD. 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 P9WF33 SwissProt · reviewed · Evidence at protein level
UniProt nameTyrosine recombinase XerD
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.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category D Cell cycle control, cell division, chromosome partitioning
Preferred namexerD
eggNOG descriptionTyrosine recombinase XerD
Orthologous groupCOG4974
KEGG orthology K03733, K04763
Gene Ontology (2) GO:0008150, GO:0040007

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 0.262 · purifying
Polymorphic sites (≥ 0.1% of strains) 3 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
Phage_int_SAM_1PF02899.24 8.8e-218–98 Phage integrase, N-terminal SAM-like domain
Phage_integrasePF00589.28 8.9e-46121–294 Phage integrase family

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

Closest characterised functional partner: Rv1700 (NUDIX hydrolase), high confidence from genomic context alone (score 976 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv1700 NUDIX hydrolase 996 976 ctx neighborhood:882 coexpression:801 textmining:870
Rv1699 pyrG CTP synthase 990 932 ctx neighborhood:882 coexpression:449 textmining:860
Rv1697 steA hyp hypothetical protein 766 767 ctx neighborhood:731
Rv1698 mctB copper transporter MctB 761 761 ctx neighborhood:754
Rv1694 tlyA 16S/23S rRNA (cytidine-2'-O)-methyltransferase TlyA 646 646 ctx neighborhood:625
Rv1695 ppnK inorganic polyphosphate/ATP-NAD kinase 641 641 ctx neighborhood:625
Rv2748c ftsK DNA translocase FtsK 717 602 ctx cooccurence:596
Rv2584c apt adenine phosphoribosyltransferase 527 527 coexpression:462
Rv1696 recN DNA repair protein RecN 546 517 ctx neighborhood:503
Rv3754 tyrA prephenate dehydrogenase TyrA 496 497 coexpression:435
Rv3917c parB chromosome partitioning protein ParB 517 491 ctx cooccurence:481
Rv3242c hyp hypothetical protein 469 469 coexpression:467
Rv1423 whiA transcriptional regulator WhiA 448 448 coexpression:448
Rv3226c hyp hypothetical protein 454 434 coexpression:434
Rv3781 rfbE O-antigen/lipopolysaccharide ABC transporter ATP-binding protein RfbE 420 420 coexpression:420

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 XerD
  • MTBC0 PGAP product: site-specific tyrosine recombinase XerD
  • Pfam (hmmscan --cut_ga): Phage_int_SAM_1 PF02899.24 (E=9e-21), Phage_integrase PF00589.28 (E=9e-46)
  • (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_216217.1)
  • 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 P9WF33 (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 — 22 functional partner(s); context anchor Rv1700
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_001809|Rv1701|xerD
MKTLALQLQGYLDHLTIERGVAANTLSSYRRDLRRYSKHLEERGITDLAKVGEHDVSEFLVALRRGDPDSGTAALSAVSAARALIAVRGLHRFAAAEGLAELDVARAVRPPTPSRRLPKSLTIDEVLSLLEGAGGDKPSDGPLTLRNRAVLELLYSTGARISEAVGLDLDDIDTHARSVLLRGKGGKQRLVPVGRPAVHALDAYLVRGRPDLARRGRGTAAIFLNARGGRLSRQSAWQVLQDAAERAGITAGVSPHMLRHSFATHLLEGGADVRVVQELLGHASVTTTQIYTLVTVHALREVWAGAHPRAR