glnB Family assigned · medium auto-curated

H37Rv Rv2919c · MTBC0 mtbc0_003101 · 112 aa · 3251567–3251905 (-) · RefSeq NP_217435.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)nitrogen regulatory protein P-II
MTBC0 PGAP re-annotationnitrogen regulatory protein P-II
Revised (this work)Nitrogen regulatory protein P-II. Pfam: P-II (PF00543.28).

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

Curated reference (UniProt)

UniProt P9WN31 SwissProt · reviewed · Evidence at protein level
UniProt nameNitrogen regulatory protein P-II
Curated functionIn nitrogen-limiting conditions, when the ratio of Gln to 2-ketoglutarate decreases, P-II is uridylylated to P-II-UMP. P-II-UMP allows the deadenylation of glutamine synthetase (GS), thus activating the enzyme. Conversely, in nitrogen excess P-II is deuridylated and promotes the adenylation of GS. P-II indirectly controls the transcription of the GS gene (glnA). P-II prevents NR-II-catalyzed conversion of NR-I to NR-I-phosphate, the transcriptional activator of glnA. When P-II is uridylylated to P-II-UMP, these events are reversed (By similarity).

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category K Transcription
Preferred nameglnB
eggNOG descriptionnitrogen regulatory protein P-II
Orthologous groupCOG0347
KEGG orthology K04751
KEGG pathways map02020
Gene Ontology (34) GO:0000166, GO:0003674, GO:0005488, GO:0005524, GO:0005575, GO:0005623, GO:0005886, GO:0008144, GO:0008150, GO:0016020, GO:0017076, GO:0030554 +22 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 0.648 · 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
P-IIPF00543.28 7.7e-321–106 Nitrogen regulatory protein P-II

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

Closest characterised functional partner: amt (ammonium transporter integral membrane protein), high confidence from genomic context alone (score 1000 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv2920c amt ammonium transporter integral membrane protein 999 1000 ctx neighborhood:881 fusion:899 cooccurence:632 coexpression:859 experimental:911 textmining:634
Rv2918c glnD bifunctional uridylyltransferase/uridylyl-removing enzyme 999 996 ctx neighborhood:805 cooccurence:617 experimental:468 database:900 textmining:955
Rv1654 argB acetylglutamate kinase 952 938 experimental:928
Rv3529c hyp hypothetical protein 807 789 experimental:787
Rv2267c stf3 hyp hypothetical protein 806 788 experimental:787
Rv1691 hyp hypothetical protein 805 787 experimental:787
Rv2387 hyp hypothetical protein 718 679 experimental:652
Rv3859c gltB glutamate synthase large subunit 884 566 ctx neighborhood:544 textmining:745
Rv2921c ftsY signal recognition particle receptor FtsY 553 512 ctx neighborhood:510
Rv2922c smc chromosome partition protein Smc 486 460 ctx neighborhood:460
Rv2220 glnA1 glutamine synthetase 958 457 textmining:927
Rv2922A acyP acylphosphatase 457 457 ctx neighborhood:457
Rv1475c acn iron-regulated aconitate hydratase 462 428
Rv2923c hyp hypothetical protein 413 414 ctx neighborhood:412
Rv2924c fpg formamidopyrimidine-DNA glycosylase 420 398

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: nitrogen regulatory protein P-II
  • MTBC0 PGAP product: nitrogen regulatory protein P-II
  • Pfam (hmmscan --cut_ga): P-II PF00543.28 (E=8e-32)
  • (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_217435.1)
  • Domains: Pfam-A via hmmscan --cut_ga — P-II (PF00543.28)
  • 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 COG0347
  • Curated reference: UniProt P9WN31 (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 — 26 functional partner(s); context anchor amt
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003101|Rv2919c|glnB
MKLITAIVKPFTLDDVKTSLEDAGVLGMTVSEIQGYGRQKGHTEVYRGAEYSVDFVPKVRIEVVVDDSIVDKVVDSIVRAARTGKIGDGKVWVSPVDTIVRVRTGERGHDAL