hisH Family assigned · medium auto-curated

H37Rv Rv1602 · MTBC0 mtbc0_001708 · 206 aa · 1814628–1815248 (+) · RefSeq NP_216118.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)imidazole glycerol phosphate synthase subunit HisH
MTBC0 PGAP re-annotationimidazole glycerol phosphate synthase subunit HisH
Revised (this work)Imidazole glycerol phosphate synthase subunit HisH. Pfam: GATase (PF00117.35).

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

Curated reference (UniProt)

UniProt P9WMM1 SwissProt · reviewed · Evidence at protein level
UniProt nameImidazole glycerol phosphate synthase subunit HisH
EC (curated) EC 3.5.1.2, EC 4.3.2.10
Curated functionIGPS catalyzes the conversion of PRFAR and glutamine to IGP, AICAR and glutamate. The HisH subunit catalyzes the hydrolysis of glutamine to glutamate and ammonia as part of the synthesis of IGP and AICAR. The resulting ammonia molecule is channeled to the active site of HisF (By similarity).

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category E Amino acid transport and metabolism
Preferred namehisH
eggNOG descriptionIGPS catalyzes the conversion of PRFAR and glutamine to IGP, AICAR and glutamate. The HisH subunit provides the glutamine amidotransferase activity that produces the ammonia necessary to HisF for the synthesis of IGP and AICAR
Orthologous groupCOG0118
KEGG orthology K02501
KEGG pathways map00340, map01100, map01110, map01230
KEGG modules M00026
Gene Ontology (8) GO:0005575, GO:0005618, GO:0005623, GO:0008150, GO:0030312, GO:0040007, GO:0044464, GO:0071944

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 1.068 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 1 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
GATasePF00117.35 1.0e-187–201 Glutamine amidotransferase class-I

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

Closest characterised functional partner: hisA (1-(5-phosphoribosyl)-5-((5-phosphoribosylamino)methylideneamino)imidazole-4-carboxamide isomerase), high confidence from genomic context alone (score 1000 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv1603 hisA 1-(5-phosphoribosyl)-5-((5-phosphoribosylamino)methylideneamino)imidazole-4-carboxamide isomerase 999 1000 ctx neighborhood:876 cooccurence:765 coexpression:970 database:900 textmining:632
Rv1605 hisF imidazole glycerol phosphate synthase subunit HisF 999 1000 ctx neighborhood:876 fusion:900 cooccurence:774 coexpression:915 experimental:926 database:900 textmining:664
Rv1601 hisB imidazole glycerol-phosphate dehydratase 999 1000 ctx neighborhood:881 cooccurence:774 coexpression:958 database:900 textmining:617
Rv1599 hisD histidinol dehydrogenase 999 998 ctx neighborhood:881 cooccurence:774 coexpression:946 textmining:619
Rv1600 hisC1 histidinol-phosphate aminotransferase 998 998 ctx neighborhood:881 cooccurence:738 coexpression:931 textmining:582
Rv1606 hisI phosphoribosyl-AMP cyclohydrolase 998 998 ctx neighborhood:876 cooccurence:773 coexpression:926 textmining:492
Rv1604 impA inositol-monophosphatase ImpA 975 974 ctx neighborhood:876 coexpression:801
Rv2121c hisG ATP phosphoribosyltransferase 987 969 ctx cooccurence:762 coexpression:857 textmining:602
Rv2122c hisE phosphoribosyl-ATP pyrophosphatase 943 889 coexpression:857 textmining:517
Rv0957 purH bifunctional phosphoribosylaminoimidazolecarboxamide formyltransferase/inosinemonophosphate cyclohydrolase 839 816 database:800
Rv0777 purB adenylosuccinate lyase PurB 819 813 database:800
Rv2584c apt adenine phosphoribosyltransferase 811 812 database:800
Rv3772 hisC2 histidinol-phosphate aminotransferase 827 809 coexpression:693
Rv2231c cobC aminotransferase 813 793 coexpression:694
Rv0114 gmhB D-glycero-alpha-D-manno-heptose-1,7-bisphosphate 7-phosphatase 742 703 coexpression:679

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: imidazole glycerol phosphate synthase subunit HisH
  • MTBC0 PGAP product: imidazole glycerol phosphate synthase subunit HisH
  • Pfam (hmmscan --cut_ga): GATase PF00117.35 (E=1e-18)
  • (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_216118.1)
  • Domains: Pfam-A via hmmscan --cut_ga — GATase (PF00117.35)
  • 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 COG0118
  • Curated reference: UniProt P9WMM1 (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 — 34 functional partner(s); context anchor hisA
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_001708|Rv1602|hisH
MTAKSVVVLDYGSGNLRSAQRALQRVGAEVEVTADTDAAMTADGLVVPGVGAFAACMAGLRKISGERIIAERVAAGRPVLGVCVGMQILFACGVEFGVQTPGCGHWPGAVIRLEAPVIPHMGWNVVDSAAGSALFKGLDVDARFYFVHSYAAQRWEGSPDALLTWATYRAPFLAAVEDGALAATQFHPEKSGDAGAAVLSNWVDGL