Q76FS5 · SPS2_ARATH

Function

function

Involved in providing solanesyl diphosphate for plastoquinone-9 (PQ-9) formation in plastids (Probable) (PubMed:15784989, PubMed:23913686).
Catalyzes the elongation of the prenyl side chain of PQ-9 in plastids (PubMed:23913686).
Contributes to the biosynthesis of plastochromanol-8 (PC-8) in plastids (PubMed:23913686).
Does not contribute to the synthesis of tocopherol or ubiquinone (PubMed:23913686).
PQ-9 and PC-8 are lipophilic antioxidants that act as protectant against photooxidative stress under high light stress conditions (PubMed:23913686).
Prefers geranylgeranyl diphosphate to farnesyl diphosphate as substrate (PubMed:15784989).
No activity with geranyl diphosphate or dimethylallyl diphosphate as substrate (PubMed:15784989).

Catalytic activity

Cofactor

Mg2+ (UniProtKB | Rhea| CHEBI:18420 )

Note: Binds 2 Mg2+ ions per subunit.

Kinetics

KM SUBSTRATE pH TEMPERATURE[C] NOTES EVIDENCE
6.89 μMfarnesyl diphosphatein the presence of 500 uM of isopentenyl diphosphate
0.843 μMgeranylgeranyl diphosphatein the presence of 100 uM of isopentenyl diphosphate
182 μMisopentenyl diphosphatein the presence of 20 uM of farnesyl diphosphate
28.9 μMisopentenyl diphosphatein the presence of 4 uM of geranylgeranyl diphosphate
kcat is 3.77 sec-1 with farnesyl diphosphate as substrate (in the presence of 500 uM of isopentenyl diphosphate). kcat is 2.33 sec-1 with geranylgeranyl diphosphate as substrate (in the presence of 100 uM of isopentenyl diphosphate). kcat is 2.83 sec-1 with isopentenyl diphosphate as substrate (in the presence of 20 uM of farnesyl diphosphate). kcat is 1.72 sec-1 with isopentenyl diphosphate as substrate (in the presence of 4 uM of geranylgeranyl diphosphate).

pH Dependence

Optimum pH is 8.0.

Features

Showing features for binding site.

TypeIDPosition(s)Description
Binding site137isopentenyl diphosphate (UniProtKB | ChEBI)
Binding site140isopentenyl diphosphate (UniProtKB | ChEBI)
Binding site175isopentenyl diphosphate (UniProtKB | ChEBI)
Binding site182Mg2+ 1 (UniProtKB | ChEBI)
Binding site182Mg2+ 2 (UniProtKB | ChEBI)
Binding site186Mg2+ 1 (UniProtKB | ChEBI)
Binding site186Mg2+ 2 (UniProtKB | ChEBI)
Binding site191an all-trans-polyprenyl diphosphate (UniProtKB | ChEBI)
Binding site192isopentenyl diphosphate (UniProtKB | ChEBI)
Binding site268an all-trans-polyprenyl diphosphate (UniProtKB | ChEBI)
Binding site269an all-trans-polyprenyl diphosphate (UniProtKB | ChEBI)
Binding site306an all-trans-polyprenyl diphosphate (UniProtKB | ChEBI)
Binding site323an all-trans-polyprenyl diphosphate (UniProtKB | ChEBI)

GO annotations

AspectTerm
Cellular Componentchloroplast
Cellular Componentchloroplast stroma
Cellular Componentplastid
Molecular Functionall-trans-nonaprenyl-diphosphate synthase (geranylgeranyl-diphosphate specific) activity
Molecular Functionmetal ion binding
Biological Processisoprenoid biosynthetic process
Biological Processplastoquinone biosynthetic process

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    Solanesyl diphosphate synthase 2, chloroplastic
  • EC number
  • Short names
    AtSPS2
  • Alternative names
    • All-trans-nonaprenyl-diphosphate synthase 2 (geranylgeranyl-diphosphate specific)

Gene names

    • Name
      SPS2
    • Synonyms
      SPPS
    • ORF names
      F20D23.25
    • Ordered locus names
      At1g17050

Organism names

  • Taxonomic identifier
  • Strain
    • cv. Columbia
  • Taxonomic lineage
    Eukaryota > Viridiplantae > Streptophyta > Embryophyta > Tracheophyta > Spermatophyta > Magnoliopsida > eudicotyledons > Gunneridae > Pentapetalae > rosids > malvids > Brassicales > Brassicaceae > Camelineae > Arabidopsis

Accessions

  • Primary accession
    Q76FS5
  • Secondary accessions
    • Q84LG1
    • Q9SHG4

Proteomes

Organism-specific databases

Genome annotation databases

Subcellular Location

Keywords

Phenotypes & Variants

Disruption phenotype

Reduced growth (PubMed:23913686).
Decreased levels of plastoquinone-9 (PQ-9) and complete loss of plastochromanol-8 (PC-8) in leaves (PubMed:23913686).
Severe increase of photoinhibition at high light intensity (PubMed:23913686).
The double mutants sps1 and sps2 exhibit an albino phenotype and are devoided of both PQ-9 and PC-8 in cotyledons (PubMed:23913686).

Variants

We now provide the "Disease & Variants" viewer in its own tab.

The viewer provides 20 variants from UniProt as well as other sources including ClinVar and dbSNP.

Go to variant viewer

PTM/Processing

Features

Showing features for transit peptide, chain.

TypeIDPosition(s)Description
Transit peptide1-60Chloroplast
ChainPRO_000041484961-417Solanesyl diphosphate synthase 2, chloroplastic

Proteomic databases

Expression

Tissue specificity

Higher expression in leaves than in roots.

Induction

Induced by high light conditions.

Gene expression databases

Interaction

Subunit

Homodimer (By similarity).
Interacts with FBN5 (PubMed:26432861).

Protein-protein interaction databases

Structure

Family & Domains

Sequence similarities

Belongs to the FPP/GGPP synthase family.

Keywords

Phylogenomic databases

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Sequence processing
    The displayed sequence is further processed into a mature form.
  • Length
    417
  • Mass (Da)
    46,045
  • Last updated
    2004-07-05 v1
  • Checksum
    E62BA8786A2548BB
MMMSCRNIDLGTSVLDHSCSSSSTSRRFLFGNSSKTVCMIGGRSCVGNLVFLRRDLATCRAVPAKSKENSLVNGIGQDQTVMLNLRQESRKPISLETLFEVVADDLQRLNDNLLSIVGAENPVLISAAEQIFSAGGKRMRPGLVFLVSRATAELAGLKELTVEHRRLGEIIEMIHTASLIHDDVLDESDMRRGRETVHELFGTRVAVLAGDFMFAQASWYLANLENLEVIKLISQVIKDFASGEIKQASSLFDCDVKLDDYMLKSYYKTASLVAASTKGAAIFSKVESKVAEQMYQFGKNLGLSFQVVDDILDFTQSTEQLGKPAANDLAKGNITAPVIFALENEPRLREIIESEFCEPGSLEEAIEIVRNRGGIKKAQELAKEKAELALKNLNCLPRSGFRSALEDMVMFNLERID

Sequence caution

The sequence AAD50025.1 differs from that shown. Reason: Erroneous initiation Truncated N-terminus.

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
AB104727
EMBL· GenBank· DDBJ
BAC82428.1
EMBL· GenBank· DDBJ
mRNA
AB188498
EMBL· GenBank· DDBJ
BAD88534.1
EMBL· GenBank· DDBJ
mRNA
AC007651
EMBL· GenBank· DDBJ
AAD50025.1
EMBL· GenBank· DDBJ
Genomic DNA Different initiation
CP002684
EMBL· GenBank· DDBJ
AEE29535.1
EMBL· GenBank· DDBJ
Genomic DNA
BT028962
EMBL· GenBank· DDBJ
ABI54337.1
EMBL· GenBank· DDBJ
mRNA
BT004246
EMBL· GenBank· DDBJ
AAO42250.1
EMBL· GenBank· DDBJ
mRNA

Genome annotation databases

Similar Proteins

Disclaimer

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