thrB Resolved · high auto-curated

H37Rv Rv1296 · MTBC0 mtbc0_001388 · 316 aa · 1461036–1461986 (+) · RefSeq NP_215812.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)homoserine kinase
MTBC0 PGAP re-annotationhomoserine kinase
Revised (this work)Homoserine kinase. Pfam: GHMP_kinases_N (PF00288.33), GHMP_kinases_C (PF08544.19).

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

Curated reference (UniProt)

UniProt P9WKE7 SwissProt · reviewed · Evidence at protein level
UniProt nameHomoserine kinase
EC (curated) EC 2.7.1.39
Curated functionCatalyzes the ATP-dependent phosphorylation of L-homoserine to L-homoserine phosphate.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category E Amino acid transport and metabolism
Preferred namethrB
eggNOG descriptionCatalyzes the ATP-dependent phosphorylation of L- homoserine to L-homoserine phosphate
Orthologous groupCOG0083
EC number EC 2.7.1.39
KEGG orthology K00872
KEGG pathways map00260, map01100, map01110, map01120, map01230
KEGG modules M00018
Gene Ontology (55) GO:0000096, GO:0000097, GO:0003674, GO:0003824, GO:0004413, GO:0005575, GO:0005622, GO:0005623, GO:0005737, GO:0005829, GO:0006082, GO:0006520 +43 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 0.225 · purifying
Polymorphic sites (≥ 0.1% of strains) 5 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
GHMP_kinases_NPF00288.33 4.7e-1469–154 GHMP kinases N terminal domain
GHMP_kinases_CPF08544.19 1.6e-05231–283 GHMP kinases C terminal

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

Closest characterised functional partner: thrC (threonine synthase), high confidence from genomic context alone (score 998 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv1295 thrC threonine synthase 999 998 ctx neighborhood:731 coexpression:920 database:900 textmining:709
Rv1294 thrA homoserine dehydrogenase 999 997 ctx neighborhood:731 coexpression:875 database:900 textmining:843
Rv0809 purM phosphoribosylformylglycinamidine cyclo-ligase PurM 909 899 ctx fusion:898
Rv0069c sdaA L-serine dehydratase 860 843 database:800
Rv2210c ilvE branched-chain amino acid aminotransferase 866 827 database:800
Rv2124c metH methionine synthase 894 826 database:800 textmining:421
Rv1293 lysA diaminopimelate decarboxylase 948 819 ctx neighborhood:731 textmining:725
Rv0391 metZ O-succinylhomoserine sulfhydrylase 839 818 database:800
Rv1079 metB cystathionine gamma-synthase 838 817 database:800
Rv3340 metC O-acetylhomoserine sulfhydrylase 818 811 database:800
Rv1133c metE 5-methyltetrahydropteroyltriglutamate--homocysteine methyltransferase 888 809 database:800 textmining:441
Rv0075 aminotransferase 806 807 database:800
Rv2335 cysE serine acetyltransferase 830 802 database:800
Rv3248c sahH adenosylhomocysteinase 802 802 database:800
Rv1077 cbs cystathionine beta-synthase 822 801 database:800

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: homoserine kinase
  • MTBC0 PGAP product: homoserine kinase
  • Pfam (hmmscan --cut_ga): GHMP_kinases_N PF00288.33 (E=5e-14), GHMP_kinases_C PF08544.19 (E=2e-05)
  • (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_215812.1)
  • Domains: Pfam-A via hmmscan --cut_ga — GHMP_kinases_N (PF00288.33), GHMP_kinases_C (PF08544.19)
  • 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 COG0083
  • Curated reference: UniProt P9WKE7 (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 — 58 functional partner(s); context anchor thrC
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_001388|Rv1296|thrB
MVTQALLPSGLVASAVVAASSANLGPGFDSVGLALSLYDEIIVETTDSGLTVTVDGEGGDQVPLGPEHLVVRAVQHGLQAAGVSAAGLAVRCRNAIPHSRGLGSSAAAVVGGLAAVNGLVVQTDSSPSSDAELIQLASEFEGHPDNAAAAVLGGAVVSWTDHSGDRPNYSAVSLRLHPDIRLFTAIPEQRSSTAETRVLLPAQVSHDDARFNVSRAALLVVALTERPDLLMAATEDLLHQPQRAAAMTASAEYLRLLRRHNVAAALSGAGPSLIALSTDSELPTDAVEFGAAKGFAVTELTVGEAVRWSPTVRVPG