MAM3 (At5g23020, formerly MAM-L, Q9FN52) review notes

Activity

Localization and genetics

Curation decisions

2026-10-01: GO:0033322 withdrawn

The NEW annotation to GO:0033322 (L-homomethionine biosynthetic process) has been removed, and the
term dropped from core_functions. GO obsoleted the sibling terms GO:0033506 ("glucosinolate
biosynthetic process from homomethionine": "a specific pathway variant, which is out of scope for
GO", replaced by GO:0019761) and GO:0033321 ("homomethionine metabolic process": "an unnecessary
grouping term"). No gene product in any species carries GO:0033322. Read together, this is a GO
convention to annotate the chain-elongation enzymes to glucosinolate biosynthetic process
(GO:0019761), which this gene already carries, not a gap to fill. The question is kept as a
suggested_question for GO.

2026-10-25 independent chain-elongation audit

Re-examined every existing annotation and core against the primary studies and exact GO reactions; preserved all machine-sourced fields and prior rows. Normal fetch-gene and fetch-gene-pmids completed. The default Falcon attempt for this panel (MAM1) failed authentication and perplexity-lite failed insufficient quota; no fabricated provider report was created. Existing provider reports were contextual only; primary sources govern decisions. Plant proteins do not require bacterial fitness fetches.

Correct broad terms now refine to supported descendants. IIL1 and SSU3 catalytic claims refer to heterodimers, with contributes_to in cores; catalytic-site ownership alone does not establish autonomous subunit activity. MAM1 lacks measured IPMS activity, whereas MAM3 retains a weak non-core activity without established native leucine-pathway participation. IMDH1 biochemical comparisons distinguish its specialized methylthioalkylmalate substrate from 3-isopropylmalate; IPMDH2 structural data are not direct IMDH1 structures. BCAT3 terminal transamination is distinct from unelongated methionine transamination and does not establish exclusivity over all chain lengths.