NaAO2_candidate_AO_1 Notes

• UniProt curates A0A314LIN0 as an L-aspartate oxidase/NadB-family flavoprotein that catalyzes oxidation of L-aspartate to iminoaspartate, placing it in the same upstream NAD-derived chemistry that can feed pyridine alkaloid biosynthesis. [file:NICAT/NaAO2_candidate_AO_1/NaAO2_candidate_AO_1-uniprot.txt "DE RecName: Full=L-aspartate oxidase"; "CC -!- CATALYTIC ACTIVITY: Reaction=L-aspartate + O2 = iminosuccinate + H2O2"; "CC -!- PATHWAY: Alkaloid biosynthesis."; "CC -!- PATHWAY: Cofactor biosynthesis; NAD(+) biosynthesis; iminoaspartate from L-aspartate (oxidase route): step 1/1."]
• UniProt places this candidate in plastid/chloroplast and in the NadB subfamily, so AO_1 is a credible biochemical candidate but still looks like a generic duplicated aspartate oxidase without additional pathway-discriminating evidence. [file:NICAT/NaAO2_candidate_AO_1/NaAO2_candidate_AO_1-uniprot.txt "CC -!- SUBCELLULAR LOCATION: Plastid, chloroplast"; "CC -!- SIMILARITY: Belongs to the FAD-dependent oxidoreductase 2 family. NadB subfamily."]
• The N. attenuata genome paper explicitly frames nicotine biosynthesis as an innovation assembled from duplicated NAD and polyamine pathways, which is consistent with having more than one AO-like paralog in the genome. PMID:28536194
• The full glucosylation preprint keeps AO-like genes connected to the nicotine module by listing AO2B among the stronger tobacco genes correlated with A622, but it still does not identify which NICAT AO paralog is specialized. [file:projects/NICOTINE_BIOSYNTHESIS/biorxiv-nicotine-glucosylation-notes.md "genes most correlated with A622 include MATE1, PMT3, PMT2, PMT1, beta-GD1, AO2B, and MPO1"; "QPT2 and AO2 are supported at the level of coordinated pathway expression and pathway framing, but this paper does not directly assay their enzymatic roles."]
• AO_1 remains a plausible NaAO2 candidate, but the present public annotations do not justify treating both AO_0 and AO_1 as equally core without further paralog-resolution evidence. [file:NICAT/NaAO2_candidate_AO_1/NaAO2_candidate_AO_1-uniprot.txt "GN Name=AO_1"; "CC -!- PATHWAY: Alkaloid biosynthesis."]