amt Resolved · high auto-curated

H37Rv Rv2920c · MTBC0 mtbc0_003102 · 477 aa · 3251902–3253335 (-) · RefSeq NP_217436.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)ammonium transporter integral membrane protein
MTBC0 PGAP re-annotationammonium transporter
Revised (this work)Ammonium transporter. Pfam: Ammonium_transp (PF00909.27).

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

Curated reference (UniProt)

UniProt P9WQ65 SwissProt · reviewed · Inferred from homology
UniProt nameAmmonium transporter
Curated functionInvolved in the uptake of ammonium/ammonia (NH(4)(+)/NH(3)).

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category U Intracellular trafficking, secretion and vesicular transport
Preferred nameamtB
eggNOG descriptionAmmonium Transporter
Orthologous groupCOG0004
KEGG orthology K03320

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) pseudogene candidate

pN/pS 0.943 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 3 synonymous, 7 missense, 1 nonsense, 0 frameshift
Disruption 1 distinct premature-stop/frameshift site(s); most common in 1.38% of strains (2009) · clonal

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
Ammonium_transpPF00909.27 9.6e-13216–441 Ammonium Transporter Family

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

Closest characterised functional partner: glnB (nitrogen regulatory protein P-II), high confidence from genomic context alone (score 1000 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv2919c glnB nitrogen regulatory protein P-II 999 1000 ctx neighborhood:881 fusion:899 cooccurence:632 coexpression:859 experimental:911 textmining:634
Rv2918c glnD bifunctional uridylyltransferase/uridylyl-removing enzyme 937 842 ctx neighborhood:805 textmining:621
Rv3859c gltB glutamate synthase large subunit 947 801 ctx neighborhood:544 cooccurence:438 textmining:745
Rv2921c ftsY signal recognition particle receptor FtsY 673 658 ctx neighborhood:651
Rv2923c hyp hypothetical protein 655 655 ctx neighborhood:647
Rv2922c smc chromosome partition protein Smc 627 613 ctx neighborhood:613
Rv2922A acyP acylphosphatase 516 517 ctx neighborhood:514
Rv1475c acn iron-regulated aconitate hydratase 577 514 coexpression:443
Rv1626 pdtaR two-component system transcriptional regulator 528 461 coexpression:417
Rv1858 modB molybdenum ABC transporter permease ModB 436 436 coexpression:426
Rv1857 modA molybdate ABC transporter substrate-binding lipoprotein ModA 480 420 coexpression:417
Rv0133 GCN5-like N-acetyltransferase 412 413 coexpression:402
Rv1878 glnA3 glutamine synthetase GlnA 647 412 textmining:424
Rv2222c glnA2 glutamine synthetase 748 409 textmining:591
Rv2860c glnA4 glutamine synthetase 744 406 textmining:587

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: ammonium transporter integral membrane protein
  • MTBC0 PGAP product: ammonium transporter
  • Pfam (hmmscan --cut_ga): Ammonium_transp PF00909.27 (E=1e-131)
  • (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_217436.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Ammonium_transp (PF00909.27)
  • 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 COG0004
  • Curated reference: UniProt P9WQ65 (SwissProt, reviewed; Inferred from homology)
  • 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 glnB
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003102|Rv2920c|amt
MDQFPIMGVPDGGDTAWMLVSSALVLLMTPGLAFFYGGMVRSKSVLNMIMMSISAMGVVTVLWALYGYSIAFGDDVGNIAGNPSQYWGLKGLIGVNAVAADPSTQTAAVNIPLAGTLPATVFVAFQLMFAIITVALISGAVADRLKFGAWLLFAGLWATFVYFPVAHWVFAFDGFAAEHGGWIANKLHAIDFAGGTAVHINAGVAALMLAIVLGKRRGWPATLFRPHNLPFVMLGAALLWFGWYGFNAGSATTANGVAGATFVTTTIATAAAMLGWLLTERVRDGKATTLGAASGIVAGLVAITPSCSSVNVLGALAVGVSAGVLCALAVGLKFKLGFDDSLDVVGVHLVGGLVGTLLVGLLAAPEAPAINGVAGVSKGLFYGGGFAQLERQALGACSVLVYSGIITLILALILKFTIGLRLDAEQESTGIDEAEHAESGYDFAVASGSVLPPRVTVEDSRNGIQERIGQKVEAEPK