ppk1 Resolved · high auto-curated

H37Rv Rv2984 · MTBC0 mtbc0_003169 · 742 aa · 3361163–3363391 (+) · RefSeq NP_217500.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)polyphosphate kinase
MTBC0 PGAP re-annotationRNA degradosome polyphosphate kinase
Revised (this work)RNA degradosome polyphosphate kinase. Pfam: PP_kinase_N (PF13089.12), PP_kinase (PF02503.23), PP_kinase_C_1 (PF17941.8), PP_kinase_C (PF13090.13), PLDc_2 (PF13091.13).

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

Curated reference (UniProt)

UniProt P9WHV9 SwissProt · reviewed · Evidence at protein level
UniProt namePolyphosphate kinase
EC (curated) EC 2.7.4.1
Curated functionCatalyzes the reversible transfer of the terminal phosphate of ATP to form a long-chain polyphosphate (polyP).

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category P Inorganic ion transport and metabolism
Preferred nameppk
eggNOG descriptionCatalyzes the reversible transfer of the terminal phosphate of ATP to form a long-chain polyphosphate (polyP)
Orthologous groupCOG0855
EC number EC 2.7.4.1
KEGG orthology K00937
KEGG pathways map00190, map03018
Gene Ontology (61) GO:0000287, GO:0001666, GO:0003674, GO:0003824, GO:0005488, GO:0005575, GO:0005623, GO:0005886, GO:0006464, GO:0006468, GO:0006793, GO:0006796 +49 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 0.662 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 2 synonymous, 4 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
PP_kinase_NPF13089.12 3.0e-3853–159 Polyphosphate kinase N-terminal domain
PP_kinasePF02503.23 1.5e-66168–357 Polyphosphate kinase middle domain
PP_kinase_C_1PF17941.8 8.7e-74386–552 Polyphosphate kinase C-terminal domain 1
PP_kinase_CPF13090.13 2.9e-54559–726 Polyphosphate kinase C-terminal domain 2
PLDc_2PF13091.13 1.7e-07590–701 PLD-like domain

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

Closest characterised functional partner: ppk2 (polyphosphate kinase), high confidence from genomic context alone (score 954 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv3232c ppk2 polyphosphate kinase 994 954 ctx cooccurence:512 database:900 textmining:895
Rv3628 ppa inorganic pyrophosphatase 944 900 database:900 textmining:462
Rv2985 mutT1 8-oxo-dGTP diphosphatase 824 818 ctx neighborhood:783
Rv0819 mshD mycothiol acetyltransferase 815 815 ctx fusion:783
Rv0496 ppx1 hyp hypothetical protein 968 814 ctx cooccurence:432 coexpression:643 textmining:839
Rv1026 ppx2 hyp hypothetical protein 965 793 ctx cooccurence:406 coexpression:646 textmining:841
Rv2983 cofC 2-phospho-L-lactate guanylyltransferase 779 779 ctx neighborhood:777
Rv2982c gpdA2 glycerol-3-phosphate dehydrogenase 711 711 ctx neighborhood:708
Rv1629 polA DNA polymerase I 538 495 coexpression:425
Rv2981c ddlA D-alanine--D-alanine ligase 597 474 ctx neighborhood:472
Rv2090 5'-3' exonuclease 499 265
Rv2702 ppgK polyphosphate glucokinase 424 197
Rv0933 pstB phosphate ABC transporter ATP-binding protein PstB 401 153
Rv0930 pstA1 phosphate ABC transporter permease PstA 412 151
Rv3509c ilvX acetohydroxyacid synthase large subunit 459 77 textmining:439

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: polyphosphate kinase
  • MTBC0 PGAP product: RNA degradosome polyphosphate kinase
  • Pfam (hmmscan --cut_ga): PP_kinase_N PF13089.12 (E=3e-38), PP_kinase PF02503.23 (E=2e-66), PP_kinase_C_1 PF17941.8 (E=9e-74), PP_kinase_C PF13090.13 (E=3e-54), PLDc_2 PF13091.13 (E=2e-07)
  • (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_217500.1)
  • Domains: Pfam-A via hmmscan --cut_ga — PP_kinase_N (PF13089.12), PP_kinase (PF02503.23), PP_kinase_C_1 (PF17941.8), PP_kinase_C (PF13090.13), PLDc_2 (PF13091.13)
  • 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 COG0855
  • Curated reference: UniProt P9WHV9 (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 — 28 functional partner(s); context anchor ppk2
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003169|Rv2984|ppk1
MMSNDRKVTEIENSPVTEVRPEEHAWYPDDSALAAPPAATPAAISDQLPSDRYLNRELSWLDFNARVLALAADKSMPLLERAKFLAIFASNLDEFYMVRVAGLKRRDEMGLSVRSADGLTPREQLGRIGEQTQQLASRHARVFLDSVLPALGEEGIYIVTWADLDQAERDRLSTYFNEQVFPVLTPLAVDPAHPFPFVSGLSLNLAVTVRQPEDGTQHFARVKVPDNVDRFVELAAREASEEAAGTEGRTALRFLPMEELIAAFLPVLFPGMEIVEHHAFRITRNADFEVEEDRDEDLLQALERELARRRFGSPVRLEIADDMTESMLELLLRELDVHPGDVIEVPGLLDLSSLWQIYAVDRPTLKDRTFVPATHPAFAERETPKSIFATLREGDVLVHHPYDSFSTSVQRFIEQAAADPNVLAIKQTLYRTSGDSPIVRALIDAAEAGKQVVALVEIKARFDEQANIAWARALEQAGVHVAYGLVGLKTHCKTALVVRREGPTIRRYCHVGTGNYNSKTARLYEDVGLLTAAPDIGADLTDLFNSLTGYSRKLSYRNLLVAPHGIRAGIIDRVEREVAAHRAEGAHNGKGRIRLKMNALVDEQVIDALYRASRAGVRIEVVVRGICALRPGAQGISENIIVRSILGRFLEHSRILHFRAIDEFWIGSADMMHRNLDRRVEVMAQVKNPRLTAQLDELFESALDPCTRCWELGPDGQWTASPQEGHSVRDHQESLMERHRSP