sepiapterin reductase; 7,8-dihydrobiopterin:NADP+oxidoreductase (SPR)

Function

• catalyzes final one or two reductions in tetrahydrobiopterin biosynthesis to form 5,6,7,8-tetrahydrobiopterin
• in vitro phosphorylation of Ser-213 by CaMK2 does not change kinetic parameters

7,8-dihydrobiopterin + NADP+ <--> sepiapterin + NADPH

tetrahydrobiopterin + 2 NADP+
         <-->
6-pyruvoyl-5,6,7,8-tetrahydropterin + 2 NADPH

Kinetic parameters:

• KM=14.3 uM for sepiapterin
• KM=10 uM for NADPH

Structure

• homodimer
• belongs to the sepiapterin reductase family

Compartment

cytoplasm

Pathology

• depressed synthesis of tetrahydrobiopterin may play a role in a variety of human diseases

More general terms

• oxidoreductase
• phosphoprotein

Database

• UniProt: http://www.uniprot.org/uniprot/P35270.html
• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=6697
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:6697
• OMIM: https://mirror.omim.org/entry/182125