Quinolinate synthase, chloroplastic EC 18.104.22.168 Protein ONSET OF LEAF DEATH 5 Protein SULFUR E 3
UniProt gene names
QS, OLD5, SUFE3, At5g50210, K6A12.7
Refseq protein ID
TAIR protein ID
Isoform 1 (main): 718 aa
Known functions (from UniProt)
Cofactor biosynthesis; NAD(+) biosynthesis; quinolinate from iminoaspartate: step 1/1.
Homodimer (PubMed:17452319). Interacts in vitro with NFS2, CpNIFS3 and AO (PubMed:18978034). Part of a Cys defulfurase complex (Probable).
Expressed in roots, leaves, stems and flowers.
Embryonic lethality when homozygous.
The highly oxygen-sensitive (4Fe-4S) cluster at its NadA domain, can be reconstituted by its own SufE domain in the presence of NFS2, cysteine and ferrous iron.
Belongs to the quinolinate synthase A family. Type 1 subfamily.
Catalyzes the condensation of iminoaspartate with dihydroxyacetone phosphate to form quinolinate. Can complement nadA-deficient E.coli mutant. Essential for the de novo synthesis of NAD. Participates also in cysteine desulfurization mediated by NFS2. Can activate the cysteine desulfurase activity of NFS2 in vitro.
From top to bottom: Cysteine position, CSS-Palm 4.0 score, PalmPred score
Color code for cysteine position:
Predicted (high confidence prediction with CSS-Palm or/and PalmPred) / Predicted but not validated (in terms of disulfide bond and cellular location) / Not predicted
Color code for CSS-Palm 4.0: High confidence,
Color code for PalmPred: High confidence (score > 0.4),
Medium confidence (0.1 > score > 0.4),
Low confidence (score < 0.1),
GO:4260255 Iron-sulfur cluster assembly GO:4261578 Positive regulation of transferase activity GO:4261573 Aerobic respiration GO:4260276 Positive regulation of sulfur metabolic process GO:4259095 Nad biosynthetic process
GO:6477478 Transferase activity GO:4260245 Enzyme activator activity GO:4259046 Quinolinate synthetase a activity GO:6493788 Metal ion binding GO:4260260 Protein homodimerization activity GO:4260287 4 iron, 4 sulfur cluster binding