Names & Taxonomy
- Uniprot ID:
- P19623
- Entry Name:
- SPEE_HUMAN
- Status:
- reviewed
- Protein Names:
- Spermidine synthase (SPDSY) (EC 2.5.1.16) (Putrescine aminopropyltransferase)
- Gene Names:
- SRM SPS1 SRML1
- Gene Names Primary:
- SRM
- Organism:
- Homo sapiens (Human)
Structure
- Length:
- 302
- Sequence:
- MEPGPDGPAASGPAAIREGWFRETCSLWPGQALSLQVEQLLHHRRSRYQDILVFRSKTYGNVLVLDGVIQCTERDEFSYQEMIANLPLCSHPNPRKVLIIGGGDGGVLREVVKHPSVESVVQCEIDEDVIQVSKKFLPGMAIGYSSSKLTLHVGDGFEFMKQNQDAFDVIITDSSDPMGPAESLFKESYYQLMKTALKEDGVLCCQGECQWLHLDLIKEMRQFCQSLFPVVAYAYCTIPTYPSGQIGFMLCSKNPSTNFQEPVQPLTQQQVAQMQLKYYNSDVHRAAFVLPEFARKALNDVS
- Proteomes:
- UP000005640
Function
- Function:
- Catalyzes the production of spermidine from putrescine and decarboxylated S-adenosylmethionine (dcSAM). Has a strong preference for putrescine as substrate, and has very low activity towards 1,3-diaminopropane. Has extremely low activity towards spermidine.
- Pathway:
- Amine and polyamine biosynthesis; spermidine biosynthesis; spermidine from putrescine: step 1/1.
- Catalytic Activity:
- S-adenosyl 3-(methylthio)propylamine + putrescine = 5'-S-methyl-5'-thioadenosine + spermidine.
- Kinetics:
- BIOPHYSICOCHEMICAL PROPERTIES: Kinetic parameters: KM=20 uM for putrescine
- Enzyme Regulation:
- ENZYME REGULATION: The activity is thought to be regulated mainly by the availability of decarboxylated S-adenosylmethionine.
- Active Site:
- ACT_SITE 173 173 Proton acceptor.
- Cross Reference Drug Bank:
- DB00118
- Gene Ontology Go:
- cytosol
protein homodimerization activity
spermidine synthase activity
cellular nitrogen compound metabolic process
polyamine metabolic process
small molecule metabolic process
spermidine biosynthetic process - Gene Ontology Biological Process:
- cellular nitrogen compound metabolic process
polyamine metabolic process
small molecule metabolic process
spermidine biosynthetic process - Gene Ontology Molecular Function:
- protein homodimerization activity
spermidine synthase activity - Gene Ontology Cellular Component:
- cytosol
- Keywords:
- 3D-structure
Acetylation
Complete proteome
Polyamine biosynthesis
Polymorphism
Reference proteome
Spermidine biosynthesis
Transferase - Interacts With:
- P54274