Q8KES3 · SPRE_CHLTE

Function

function

Catalyzes the final reductions in tetra-hydrobiopterin biosynthesis to form 5,6,7,8-tetrahydrobiopterin.

Catalytic activity

Activity regulation

Slightly inhibited by N-acetyldopamine but not by N-acetylserotonin or melatonin.

Kinetics

KM SUBSTRATE pH TEMPERATURE[C] NOTES EVIDENCE
21 μMsepiapterin8.845
0.18 μMsepiapterin6.537
6.2 μMNADPH8.845
Vmax pH TEMPERATURE[C] NOTES EVIDENCE
12 pmol/min/mg37for the reverse reaction reducing sepapterin
For the reverse reaction, accepts L-threo-dihydrobiopterin, D-threo-dihydrobiopterin, L-threo-dihydroneopterin, dihydrotepidopterin and L-erythro-dihydrobiopterin as substrates.

pH Dependence

Optimum pH is around 8.8. Activity drops sharply above and below the optimum and is absent at pH 3 and virtually so at pH 10.6.

Temperature Dependence

Optimum temperature is 50 degrees Celsius. Stable at 25 and 50 degrees Celsius for 2 h but loses activity at 70 degrees Celsius in 20 minutes.

Features

Showing features for binding site.

TypeIDPosition(s)Description
Binding site9-15NADP+ (UniProtKB | ChEBI)
Binding site40-42NADP+ (UniProtKB | ChEBI)
Binding site66-67NADP+ (UniProtKB | ChEBI)
Binding site93NADP+ (UniProtKB | ChEBI)
Binding site99substrate
Binding site116NADP+ (UniProtKB | ChEBI)
Binding site145substrate
Binding site158NADP+ (UniProtKB | ChEBI)
Binding site158substrate
Binding site162NADP+ (UniProtKB | ChEBI)
Binding site191-196NADP+ (UniProtKB | ChEBI)
Binding site196substrate

GO annotations

AspectTerm
Cellular Componentcytoplasm
Molecular Functionnucleotide binding
Molecular Functionoxidoreductase activity

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    Sepiapterin reductase
  • EC number
  • Short names
    SPR
    ; cSR

Gene names

    • Ordered locus names
      CT0609

Organism names

Accessions

  • Primary accession
    Q8KES3

Proteomes

Subcellular Location

Keywords

Phenotypes & Variants

Features

Showing features for mutagenesis.

TypeIDPosition(s)Description
Mutagenesis99Drastically reduces activity. Complete loss of activity; when associated with A-196.
Mutagenesis196Drastically reduces activity. Complete loss of activity; when associated with A-99.

PTM/Processing

Features

Showing features for chain.

TypeIDPosition(s)Description
ChainPRO_00004241531-244Sepiapterin reductase

Interaction

Subunit

Homodimer.

Protein-protein interaction databases

Family & Domains

Sequence similarities

Phylogenomic databases

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    244
  • Mass (Da)
    27,114
  • Last updated
    2002-10-01 v1
  • Checksum
    754CE7BC0363D9DA
MKHILLITGAGKGIGRAIALEFARAARHHPDFEPVLVLSSRTAADLEKISLECRAEGALTDTITADISDMADVRRLTTHIVERYGHIDCLVNNAGVGRFGALSDLTEEDFDYTMNTNLKGTFFLTQALFALMERQHSGHIFFITSVAATKAFRHSSIYCMSKFGQRGLVETMRLYARKCNVRITDVQPGAVYTPMWGKVDDEMQALMMMPEDIAAPVVQAYLQPSRTVVEEIILRPTSGDIQDD

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
AE006470
EMBL· GenBank· DDBJ
AAM71851.1
EMBL· GenBank· DDBJ
Genomic DNA

Genome annotation databases

Similar Proteins

Disclaimer

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