| Accepted Name |
|---|
| Homospermidine synthase (spermidine-specific).
|
| Reaction catalysed |
|---|
| Spermidine + putrescine <=> sym-homospermidine + propane-1,3-diamine |
| Cofactor(s) |
|---|
| NAD.
|
| Comment(s) |
|---|
- The reaction of this enzyme occurs in three steps:
(1) NAD(+)-dependent dehydrogenation of spermidine.
(2) Transfer of the 4-aminobutylidene group from dehydrospermidine to
a second molecule of putrescine.
(3) Reduction of the imine intermediate to form homospermidine.
- Hence the overall reaction is transfer of a 4-aminobutyl group.
- This enzyme is more specific than EC 2.5.1.44 which is found in
bacteria, as it cannot use putrescine as donor of the 4-aminobutyl
group.
- Forms part of the biosynthetic pathway of the poisonous pyrrolizidine
alkaloids of the ragworts (Senecio).
|
| Cross-references |
|---|
| BRENDA | 2.5.1.45 |
| EC2PDB | 2.5.1.45 |
| PRIAM enzyme-specific profiles | 2.5.1.45 |
| KEGG Ligand Database for Enzyme Nomenclature | 2.5.1.45 |
| IUBMB Enzyme Nomenclature | 2.5.1.45 |
| IntEnz | 2.5.1.45 |
| MEDLINE | Find literature relating to 2.5.1.45 |
| MetaCyc | 2.5.1.45 |
| UniProtKB/Swiss-Prot |
|
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