| Domain | Name | Category | Type | 
	
		| IPR015576  | Spermine synthase, animal | Family | Family | 
	
		| IPR029063  | S-adenosyl-L-methionine-dependent methyltransferase | Family | Homologous superfamily | 
	
		| IPR030373  | Polyamine biosynthesis domain, conserved site | Site | Conserved site | 
	
		| IPR030374  | Polyamine biosynthesis  domain | Domain | Domain | 
	
		| IPR035246  | Spermidine synthase, tetramerisation domain | Domain | Domain | 
	
		| IPR037163  | Spermidine synthase, tetramerisation domain superfamily | Family | Homologous superfamily | 
	
		| IPR040900  | Spermine synthase, N-terminal | Domain | Domain |