IUBMB Enzyme Nomenclature


Accepted name: caldopentamine synthase

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

Glossary: caldopentamine = N-(3-aminopropyl)-N'-{3-[(3-aminopropyl)amino]propyl}-1,3-propanediamine
norspermidine = N-(3-aminopropyl)-1,4-butanediamine
norspermine = N,N'-bis(3-aminopropyl)-1,3-propanediamine
spermidine = N-(3-aminopropyl)-1,4-butanediamine
thermospermine = N-{3-[(3-aminopropyl)amino]propyl}-1,4-butanediamine

Other name(s): long-chain polyamine synthase (ambiguous); S-adenosyl 3-(methylthio)propylamine:norspermine 3-aminopropyltransferase

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

Comments: The enzyme, characterized from the thermophilic archaeon Hyperthermus butylicus, can also synthesize norspermine from norspermidine and thermospermine from spermidine (with lower activity). The long-chain polyamines stabilize double-stranded DNA at high temperatures. In contrast to EC, sym-norspermidine synthase and EC, norspermine synthase, this enzyme shows no activity with propane-1,3-diamine.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:


1. Knott, J.M. Biosynthesis of long-chain polyamines by crenarchaeal polyamine synthases from Hyperthermus butylicus and Pyrobaculum aerophilum. FEBS Lett 583 (2009) 3519-3524. [PMID: 19822146]

[EC created 2014]

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