SerA is an NAD-dependent D-3-phosphoglycerate dehydrogenase that oxidizes 3-phosphoglycerate to 3-phosphohydroxypyruvate in the first reaction of phosphorylated L-serine biosynthesis. It is also predicted to interconvert (R)-2-hydroxyglutarate and 2-oxoglutarate. A C-terminal ACT domain suggests potential amino-acid feedback regulation, but its effector response has not been tested in KT2440.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
| GO:0004617 phosphoglycerate dehydrogenase activity | IEA GO_REF:0000120 | ACCEPT | Summary: Accept the enzyme-specific function by conserved-family inference from characterized phosphoglycerate dehydrogenases. Reason: Q88CM5 has the expected D-isomer-specific dehydrogenase architecture, including a nucleotide-binding domain, and characterized enzymes catalyze the 3-phosphoglycerate/phosphohydroxypyruvate reaction. Supporting Evidence: file:PSEPK/serA/serA-uniprot.txt cd12176; PGDH_3 PMID:22023909 D-3-phosphoglycerate dehydrogenase converts D-3-phosphoglycerate into phosphohydroxypyruvate (PHP) |
| GO:0006564 L-serine biosynthetic process | IEA GO_REF:0000117 | ACCEPT | Summary: Accept by conserved reaction-role inference within the phosphorylated L-serine pathway. Reason: The characterized phosphoglycerate-dehydrogenase reaction supplies the first intermediate of the conserved three-step biosynthetic route. Supporting Evidence: PMID:22023909 The phosphorylated pathway is the only anabolic source of L-serine in most organisms. |
| GO:0016616 oxidoreductase activity, acting on the CH-OH group of donors, NAD or NADP as acceptor | IEA GO_REF:0000002 | MODIFY | Summary: The chemistry is correct but the term is a broad parent of the enzyme-specific phosphoglycerate dehydrogenase activity. Reason: GO:0004617 captures the same reaction at substrate-level specificity. Proposed replacements: phosphoglycerate dehydrogenase activity |
| GO:0047545 (S)-2-hydroxyglutarate dehydrogenase activity | IEA GO_REF:0000117 | REMOVE | Summary: Wrong hydroxyglutarate stereoisomer for the assigned EC reaction. Reason: The entry assigns (R)-2-hydroxyglutarate dehydrogenase activity (GO:0120568), not the (S)-2-hydroxyglutarate activity represented here. Supporting Evidence: file:PSEPK/serA/serA-uniprot.txt Reaction=(R)-2-hydroxyglutarate + NAD(+) = 2-oxoglutarate + NADH + |
| GO:0051287 NAD binding | IEA GO_REF:0000002 | KEEP AS NON CORE | Summary: Retain as a non-core cofactor-binding property distinct from the substrate-specific catalytic activity. Reason: Q88CM5 contains NAD(P)-binding Rossmann-like and D-isomer-dehydrogenase nucleotide-binding domains. Supporting Evidence: file:PSEPK/serA/serA-uniprot.txt NAD(P)-binding Rossmann-like Domain |
| GO:0120568 (R)-2-hydroxyglutarate (NAD+) dehydrogenase activity | IEA GO_REF:0000120 | MARK AS OVER ANNOTATED | Summary: The predicted secondary activity is not established for Q88CM5. Reason: UniProt assigns EC 1.1.1.399 and an alternative 2-oxoglutarate reductase name through automated rules, but direct KT2440 biochemical or physiological evidence is not available and this activity varies among phosphoglycerate dehydrogenases. |
Loading supporting content…
Download this section (compressed HTML)Q: Does KT2440 SerA carry physiologically relevant (R)-2-hydroxyglutarate dehydrogenase flux in vivo?
Q: Does the Q88CM5 ACT domain confer L-serine feedback inhibition, and what effector concentration range controls pathway flux in KT2440?
Experiment: Test a clean serA deletion for serine auxotrophy and restore growth by L-serine supplementation or gene complementation.
Loading supporting content…
Download this section (compressed HTML)Loading supporting content…
Download this section (compressed HTML)