IUBMB Enzyme Nomenclature


Accepted name: spermidine synthase

Reaction: S-adenosyl 3-(methylsulfanyl)propylamine + putrescine = S-methyl-5'-thioadenosine + spermidine

For diagram of reaction click here.

Glossary: spermidine = N-(3-aminopropyl)butane-1,4-diamine
spermine = N,N'-bis(3-aminopropyl)butane-1,4-diamine
putrescine = butane-1,4-diamine
S-adenosyl 3-(methylsulfanyl)propylamine = (3-aminopropyl){[(2S,3S,4R,5R)-5-(6-amino-9H-purin-9-yl)-3,4-dihydroxytetrahydrofuran-2-yl]methyl}methylsulfonium

Other name(s): aminopropyltransferase; putrescine aminopropyltransferase; spermidine synthetase; SpeE (ambiguous); S-adenosylmethioninamine:putrescine 3-aminopropyltransferase; S-adenosyl 3-(methylthio)propylamine:putrescine 3-aminopropyltransferase

Systematic name: S-adenosyl 3-(methylsulfanyl)propylamine:putrescine 3-aminopropyltransferase

Comments: The enzymes from the plant Glycine max and from mammalia are highly specific for putrescine as the amine acceptor [2,7]. The enzymes from the bacteria Escherichia coli and Thermotoga maritima prefer putrescine but are more tolerant towards other amine acceptors, such as spermidine and cadaverine [5,6]. cf. EC (spermine synthase) and EC (sym-norspermidine synthase).

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 37277-82-0


1. Hannonen, P., Janne, J. and Raina, A. Partial purification and characterization of spermine synthase from rat brain. Biochim. Biophys. Acta 289 (1972) 225-231. [PMID: 4564056]

2. Pegg, A.E., Shuttleworth, K. and Hibasami, H. Specificity of mammalian spermidine synthase and spermine synthase. Biochem. J. 197 (1981) 315-320. [PMID: 6798961]

3. Tabor, C.W. Propylamine transferase (spermidine synthesis). Methods Enzymol. 5 (1962) 761-765.

4. Tabor, H. and Tabor, C.W. Biosynthesis and metabolism of 1,4-diaminobutane, spermidine, spermine, and related amines. Adv. Enzymol. Relat. Areas Mol. Biol. 36 (1972) 203-268. [PMID: 4628436]

5. Bowman, W.H., Tabor, C.W. and Tabor, H. Spermidine biosynthesis. Purification and properties of propylamine transferase from Escherichia coli. J. Biol. Chem. 248 (1973) 2480-2486. [PMID: 4572733]

6. Korolev, S., Ikeguchi, Y., Skarina, T., Beasley, S., Arrowsmith, C., Edwards, A., Joachimiak, A., Pegg, A.E. and Savchenko, A. The crystal structure of spermidine synthase with a multisubstrate adduct inhibitor. Nat. Struct. Biol. 9 (2002) 27-31. [PMID: 11731804]

7. Yoon, S.O., Lee, Y.S., Lee, S.H. and Cho, Y.D. Polyamine synthesis in plants: isolation and characterization of spermidine synthase from soybean (Glycine max) axes. Biochim. Biophys. Acta 1475 (2000) 17-26. [PMID: 10806333]

[EC created 1972, modified 1982, modified 2013]

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