P50214 · IDH_NOSS1
- ProteinIsocitrate dehydrogenase [NADP]
- Geneicd
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids473 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Catalyzes the oxidative decarboxylation of isocitrate to 2-oxoglutarate and carbon dioxide with the concomitant reduction of NADP+.
Catalytic activity
- D-threo-isocitrate + NADP+ = 2-oxoglutarate + CO2 + NADPH
Cofactor
Mn2+ (UniProtKB | Rhea| CHEBI:29035 )
Note: Binds 1 Mg2+ or Mn2+ ion per subunit (By similarity).
Mn2+ is the most effective divalent cation in vitro, but the enzyme can also use Mg2+, Co2+ and Ni2+, with lower efficiency (PubMed:8169222).
Mn2+ is the most effective divalent cation in vitro, but the enzyme can also use Mg2+, Co2+ and Ni2+, with lower efficiency (PubMed:8169222).
Activity regulation
Inhibited by either oxaloacetate or glyoxylate (PubMed:8169222).
Also inhibited by the adenine nucleotides AMP, ADP and ATP and by NADPH, which inhibits the activity by 28% when it is added to the assay mixture at 0.25 mM (PubMed:8169222).
Also inhibited by the adenine nucleotides AMP, ADP and ATP and by NADPH, which inhibits the activity by 28% when it is added to the assay mixture at 0.25 mM (PubMed:8169222).
Kinetics
KM | SUBSTRATE | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|---|
4.2 μM | D,L-isocitrate | in the presence of Mn2+ | ||||
61.2 μM | D,L-isocitrate | in the presence of Mg2+ | ||||
9.3 μM | NADP+ | in the presence of Mn2+ | ||||
13.6 μM | NADP+ | in the presence of Mg2+ |
pH Dependence
Optimum pH is 8.5 (PubMed:8169222).
Shows 75% of maximal activity between pH 7.5 and 9.5 (PubMed:8169222).
Shows 75% of maximal activity between pH 7.5 and 9.5 (PubMed:8169222).
Features
Showing features for binding site, site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 104 | NADP+ (UniProtKB | ChEBI) | ||||
Sequence: T | ||||||
Binding site | 113 | D-threo-isocitrate (UniProtKB | ChEBI) | ||||
Sequence: S | ||||||
Binding site | 115 | D-threo-isocitrate (UniProtKB | ChEBI) | ||||
Sequence: N | ||||||
Binding site | 119 | D-threo-isocitrate (UniProtKB | ChEBI) | ||||
Sequence: R | ||||||
Binding site | 129 | D-threo-isocitrate (UniProtKB | ChEBI) | ||||
Sequence: R | ||||||
Binding site | 153 | D-threo-isocitrate (UniProtKB | ChEBI) | ||||
Sequence: R | ||||||
Site | 160 | Critical for catalysis | ||||
Sequence: Y | ||||||
Site | 237 | Critical for catalysis | ||||
Sequence: K | ||||||
Binding site | 362 | Mg2+ (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 394-400 | NADP+ (UniProtKB | ChEBI) | ||||
Sequence: HGTAPKH | ||||||
Binding site | 407 | NADP+ (UniProtKB | ChEBI) | ||||
Sequence: N | ||||||
Binding site | 446 | NADP+ (UniProtKB | ChEBI) | ||||
Sequence: Y | ||||||
Binding site | 450 | NADP+ (UniProtKB | ChEBI) | ||||
Sequence: R |
GO annotations
Aspect | Term | |
---|---|---|
Molecular Function | isocitrate dehydrogenase (NADP+) activity | |
Molecular Function | magnesium ion binding | |
Molecular Function | NAD binding | |
Biological Process | glyoxylate cycle | |
Biological Process | tricarboxylic acid cycle |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameIsocitrate dehydrogenase [NADP]
- EC number
- Short namesIDH
- Alternative names
Gene names
Organism names
- Strain
- Taxonomic lineageBacteria > Cyanobacteriota > Cyanophyceae > Nostocales > Nostocaceae > Nostoc
Accessions
- Primary accessionP50214
Proteomes
Phenotypes & Variants
Disruption phenotype
Essential, it cannot be deleted.
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000083547 | 1-473 | Isocitrate dehydrogenase [NADP] | |||
Sequence: MYNKITPPTTGEKITFKNGEPVVPDNPIIPFIRGDGTGIDIWPATEKVLDAAVAKAYQGKRKISWFKVYAGDEACDLYGTYQYLPEDTLTAIREYGVAIKGPLTTPVGGGIRSLNVALRQIFDLYACVRPCRYYAGTPSPHKNPEKLDVIVYRENTEDIYLGIEWKQGSEIGDRLISILNKELIPATPEHGKKQIPLDSGIGIKPISKTGSQRLVRRAIKHALTLPKDKQQVTLVHKGNIMKYTEGAFRDWGYELATSEFRQETVTERESWILSNKEKNPNISLEDNARQIDPGFDALTPEKKAQIVKEVETVLNSIWESHGNGKWKEKVLVNDRIADSIFQQIQTRPDEYSILATMNLNGDYLSDAAAAIVGGLGMGPGANIGDSCAVFEATHGTAPKHAGLDRINPGSVILSGVMMLEYMGWQEAADLIKKGLSDAIANSQVTYDLARLLEPPVEPLKCSEFADAIIKHFG |
Interaction
Structure
Sequence
- Sequence statusComplete
- Length473
- Mass (Da)52,228
- Last updated1996-10-01 v1
- ChecksumD30941B992A38AAB
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
X77654 EMBL· GenBank· DDBJ | CAA54734.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
BA000019 EMBL· GenBank· DDBJ | BAB73526.1 EMBL· GenBank· DDBJ | Genomic DNA |