General Stability | Organism |
---|---|
ADK3, like CP12, can protect GAPDH against thermal inactivation and aggregation. This ability is linked to the presence of the CP12-like extension of ADK3 as no protection is observed when this part is removed | Chlamydomonas reinhardtii |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
protein CP12 | the enzyme GapDH interacts with the intrinsically disordered protein CP12, when oxidized but not when reduced, in chloroplasts forming a stable complex. In this bienzyme complex, the activity of ADK3 is unchanged while the NADPH-dependent activity of GAPDH is significantly inhibited. CP12 acts as a chaperone for GAPDH. The NADH-dependent activity of the chloroplast GAPDH is not affected by incubation at 4°C, for between 1 and 14 h, with either oxidized ADK3 (OxADK3) or ADK3-DELTACP12 at a ratio of 2 :1 (dimeric ADK : tetrameric GAPDH). When incubated with ADK3, about 63% of the NADPH-dependent activity of GAPDH disappear and this activity is recovered by DTT. Enzyme-ADK3 interaction analysis, overview | Chlamydomonas reinhardtii |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
chloroplast | - |
Chlamydomonas reinhardtii | 9507 | - |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
D-glyceraldehyde 3-phosphate + phosphate + NAD+ | Chlamydomonas reinhardtii | - |
3-phospho-D-glyceroyl phosphate + NADH + H+ | - |
? | |
D-glyceraldehyde 3-phosphate + phosphate + NADP+ | Chlamydomonas reinhardtii | - |
3-phospho-D-glyceroyl phosphate + NADPH + H+ | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Chlamydomonas reinhardtii | P50362 | NADP-dependent glyceraldehydephosphate dehydrogenase subunit A | - |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
D-glyceraldehyde 3-phosphate + phosphate + NAD+ | - |
Chlamydomonas reinhardtii | 3-phospho-D-glyceroyl phosphate + NADH + H+ | - |
? | |
D-glyceraldehyde 3-phosphate + phosphate + NADP+ | - |
Chlamydomonas reinhardtii | 3-phospho-D-glyceroyl phosphate + NADPH + H+ | - |
? | |
additional information | glyceraldehyde-3-phosphate dehydrogenase from chloroplasts has a dual cofactor specificity and can use both NADPH and NADH | Chlamydomonas reinhardtii | ? | - |
- |
Subunits | Comment | Organism |
---|---|---|
homotetramer | in Chlamydomonas reinhardtii, the chloroplast GAPDH is a homotetrameric A4-isoform that lacks regulatory cysteine residues found in the B subunit of the heterotetrameric A2B2-GAPDH isoform | Chlamydomonas reinhardtii |
Synonyms | Comment | Organism |
---|---|---|
chloroplast glyceraldehyde-3-phosphate dehydrogenase | - |
Chlamydomonas reinhardtii |
GapA | - |
Chlamydomonas reinhardtii |
GAPDH | - |
Chlamydomonas reinhardtii |
NADP-dependent glyceraldehydephosphate dehydrogenase | - |
Chlamydomonas reinhardtii |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
22 | - |
assay at room temperature | Chlamydomonas reinhardtii |
Temperature Stability Minimum [°C] | Temperature Stability Maximum [°C] | Comment | Organism |
---|---|---|---|
4 | - |
the NADH-dependent activity of the chloroplast GAPDH is not affected by incubation at 4°C, for between 1 and 14 h, with either oxidized ADK3 (OxADK3) or ADK3-DELTACP12 at a ratio of 2:1 (dimeric ADK:tetrameric GAPDH) | Chlamydomonas reinhardtii |
43 | - |
upon heat-treatment, GAPDH becomes denatured and precipitated but ADK3 greatly improves its thermal stability, decreasing its aggregation and protecting its activity at 43°C. This ability is linked to the presence of the CP12-like extension of ADK3 as no protection is observed when this part is removed | Chlamydomonas reinhardtii |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.7 | 7.9 | assay at | Chlamydomonas reinhardtii |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
additional information | glyceraldehyde-3-phosphate dehydrogenase from chloroplasts has a dual cofactor specificity and can use both NADPH and NADH | Chlamydomonas reinhardtii | |
NAD+ | - |
Chlamydomonas reinhardtii | |
NADP+ | - |
Chlamydomonas reinhardtii |
General Information | Comment | Organism |
---|---|---|
malfunction | the enzyme GapDH interacts with the intrinsically disordered protein CP12, when oxidized but not when reduced, in chloroplasts forming a stable complex. In this bienzyme complex, the activity of ADK3 is unchanged while the NADPH-dependent activity of GAPDH is significantly inhibited. The ADK3-GAPDH bienzyme complex is unable to recruit phosphoribulokinase (PRK), in contrast with the ternary complex formed between GAPDH-CP12 and PRK. The interaction between ADK3 and GAPDH might be a mechanism to regulate the crucial ATP: NADPH ratio within chloroplasts to optimize the Calvin-Benson cycle during rapid fluctuation in environmental resources | Chlamydomonas reinhardtii |
additional information | ADK3, like CP12, can protect GAPDH against thermal inactivation and aggregation. CP12 acts as a chaperone for GAPDH. Detection o f a solubilizing effect of ADK3 on GAPDH | Chlamydomonas reinhardtii |
physiological function | in Chlamydomonas reinhardtii, the chloroplast GAPDH is a homotetrameric A4-isoform that lacks regulatory cysteine residues found in the B subunit of the heterotetrameric A2B2-GAPDH isoform. Whereas A2B2-GAPDHs from higher plants are autonomously regulated, CP12 is required to confer redox regulation to the algal A4-GAPDH. In contrast, the CP12-like tail bearing two cysteine residues present on ADK3 is not involved in its redoxregulation | Chlamydomonas reinhardtii |