tgt review notes

• Q88PL7 is a reviewed bacterial Tgt homodimer assigned to PTHR46499:SF1.
  [file:PSEPK/tgt/tgt-uniprot.txt
  "RecName: Full=Queuine tRNA-ribosyltransferase"]
  [file:interpro/panther/PTHR46499/PTHR46499-entries.csv
  "Q88PL7,Queuine tRNA-ribosyltransferase"]
• The bacterial reaction exchanges guanine 34 for preQ1. It is not the
  eukaryotic reaction that inserts free queuine. [file:PSEPK/tgt/tgt-uniprot.txt
  "queuine precursor 7-aminomethyl-7-deazaguanine (PreQ1) at position 34"]
  PMID:40703034
• QuickGO GO:0008479 (retrieved 2026-07-27) defines "guanosine34 in tRNA + queuine = guanine + queuosine34 in tRNA" and cross-references RHEA:16633,
  the free-queuine reaction.
• The repository's GOC-maintained rules apply GO:0008479 to bacterial Tgt:
  file:rules/arba/_interpro2go.txt maps IPR004803 to GO:0008479, and
  file:rules/unirule/UR000079182/UR000079182.json pairs GO:0008479 with
  EC 2.4.2.29 and the preQ1 reaction RHEA:24104.
• The review therefore accepts the existing machine-sourced GO:0008479 mapping
  with an explicit ontology-conflict caveat rather than demoting the core
  activity to broad GO:0016763. A dedicated bacterial preQ1 transglycosylase
  molecular-function term is proposed under GO:0016763.
• GO:0050147 remains unsuitable because it describes free-nucleoside
  ribosyltransferase chemistry rather than a tRNA substrate.
• The reviewed record assigns one zinc ion per subunit, so GO:0008270 zinc ion
  binding is added as a missing annotation. [file:PSEPK/tgt/tgt-uniprot.txt
  "Note=Binds 1 zinc ion per subunit."]
• Upstream preQ0 production is outside scope; Tgt receives preQ1 from QueF and
  supplies preQ1-tRNA to QueA.

OpenScientist reconciliation

Source: file:PSEPK/tgt/tgt-deep-research-openscientist.md.

• The report independently identifies Q88PL7 as bacterial Tgt and supports
  preQ1 insertion at guanine 34 rather than the eukaryotic free-queuine
  reaction.
• Its sequence, AlphaFold, operon, and pathway-completeness analyses are
  computational corroboration, not organism-specific experimental evidence.
• The report explicitly found no biochemical, structural, kinetic, or genetic
  study of Q88PL7 itself. The curated review therefore retains the existing
  orthology-based confidence level and records this as a knowledge gap.