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Your query returned 1 entry. Printable version
EC | 2.5.1.45 | ||||||
Accepted name: | homospermidine synthase (spermidine-specific) | ||||||
Reaction: | spermidine + putrescine = sym-homospermidine + propane-1,3-diamine | ||||||
For diagram of reaction, click here | |||||||
Glossary: | sym-homospermidine = N1-(4-aminobutyl)butane-1,4-diamine putrescine = butane-1,4-diamine spermidine = N1-(3-aminopropyl)butane-1,4-diamine |
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Systematic name: | spermidine:putrescine 4-aminobutyltransferase (propane-1,3-diamine-forming) | ||||||
Comments: | A eukaryotic enzyme found in plants. The reaction occurs in three steps, with some of the intermediates presumably remaining enzyme-bound: (a) NAD+-dependent dehydrogenation of spermidine to 4-iminobutan-1-amine, (b) attack by water forming 4-aminobutanal (and releasing propane-1,3-diamine), and (c) condensation of 4-aminobutanal with purescine, which forms homospermidine and restores NAD+. This enzyme is more specific than EC 2.5.1.44, homospermidine synthase, 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). | ||||||
Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc | ||||||
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