Cloned (Comment) | Organism |
---|---|
recombinant expression of His-tagged enzyme in Escherichia coli | Zea mays |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
chloroplast | - |
Zea mays | 9507 | - |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
ADP + [pyruvate, phosphate dikinase] | Zea mays | reversible phosphorylation at Thr527 and Ser528, but not Thr309 and Ser506, of PPDK | AMP + [pyruvate, phosphate dikinase] phosphate | - |
r | |
additional information | Zea mays | PPDK regulatory protein (PDRP) is a unique bifunctional enzyme, catalyzes this light-dependent regulation by reversible phosphorylation of an active-site Thr527 in PPDK | ? | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Zea mays | - |
- |
- |
Purification (Comment) | Organism |
---|---|
recombinant His-tagged enzyme from Escherichia coli | Zea mays |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
leaf | - |
Zea mays | - |
mesophyll | - |
Zea mays | - |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
ADP + [pyruvate, phosphate dikinase] | reversible phosphorylation at Thr527 and Ser528, but not Thr309 and Ser506, of PPDK | Zea mays | AMP + [pyruvate, phosphate dikinase] phosphate | - |
r | |
ADP + [pyruvate, phosphate dikinase] | i.e. recombinant His-tagged wild-type and mutant maize PPDKs as substrates, reversible phosphorylation at Thr527 and Ser528, but not Thr309 and Ser506, of PPDK. Phosphorylation is detected on wild-type PPDK, PPDK-T309A, and PPDK-S506A, but not on PPDK-T527A, PPDK-S528A, or PPDK-H529A | Zea mays | AMP + [pyruvate, phosphate dikinase] phosphate | - |
r | |
additional information | PPDK regulatory protein (PDRP) is a unique bifunctional enzyme, catalyzes this light-dependent regulation by reversible phosphorylation of an active-site Thr527 in PPDK | Zea mays | ? | - |
? | |
additional information | modeling suggests that the two hydrogen bonds between the highly conserved residues Ser528 and Gly525 are required for PDRP-mediated phosphorylation of the active-site Thr527 of PPDK, substrate PPDK three-dimensional structure analysis, overview | Zea mays | ? | - |
? |
Synonyms | Comment | Organism |
---|---|---|
PDRP | - |
Zea mays |
PPDK regulatory protein | - |
Zea mays |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
ADP | - |
Zea mays | |
AMP | - |
Zea mays |
General Information | Comment | Organism |
---|---|---|
additional information | catalytic mechanism of enzyme PDRP, overview | Zea mays |
physiological function | in C4 plants, pyruvate orthophosphate dikinase (PPDK) activity is tightly dark/light regulated by reversible phosphorylation of an active-site threonine residue. The process is catalyzed by PPDK regulatory protein (PDRP). Phosphorylation and dephosphorylation of PPDK lead to its inactivation and activation, respectively. The amount of PPDK (unphosphorylated) involved in C4 photosynthesis is indeed strictly controlled by light intensity, despite the high levels of PPDK protein that accumulate in mesophyll chloroplasts, regulation by light intensity rather than the light/dark transition. Diverse regulatory pathways may work alone or in combination to fine-tune C4PPDK activity in response to changes in lighting. Residue Ser528 plays an essential role in PDRP regulation of PPDK phosphorylation at Thr527 | Zea mays |