MAE1 notes (P36013, YKL029C)

Evidence journal (module context: gluconeogenesis; YeastCyc assigns malate + NAD+ -> pyruvate + CO2 + NADH, EC 1.1.1.38).

• Sole malic enzyme; knockout abolishes activity PMID:9603875
• Cofactor: assayed with NADP+; reported to use both PMID:9603875
• Mitochondrial PMID:9603875; matrix [UniProt:P36013]
• Role: pyruvate provision for biosynthesis, redundant with pyruvate kinase PMID:9603875

Curation decisions / module observations

• Three RCA rows assign L-malate dehydrogenase (NAD+) (EC 1.1.1.37, malate -> oxaloacetate) to Mae1p -> REMOVE (wrong reaction; MDH1-3 account for all MDH activity, PMID:1447211).
• Cytosol RCA (PWY3O-94) -> REMOVE (mitochondrial enzyme).
• Gluconeogenesis and aerobic respiration RCAs -> over-annotated: Mae1p runs malate -> pyruvate, opposite to C2 gluconeogenic flux; not a TCA enzyme.
• Module curator: MAE1 does not belong in the core of a gluconeogenesis module in S. cerevisiae; better placed as an anaplerotic/pyruvate-supply step.