The name of this superfamily has been modified since the most recent official CATH+ release (v4_3_0). At the point of the last release, this superfamily was named:
"Spermidine synthase, tetramerisation domain
".
FunFam 3: Spermidine synthase 1
Please note: GO annotations are assigned to the full protein sequence rather than individual protein domains. Since a given protein can contain multiple domains, it is possible that some of the annotations below come from additional domains that occur in the same protein, but have been classified elsewhere in CATH.
There are 5 GO terms relating to "molecular function"
			The search results have been sorted with the annotations that are found most frequently at the top of the
			list. The results can be filtered by typing text into the search box at the top of the table.
			
			
	| GO Term | Annotations | Evidence | 
|---|---|---|
| Protein binding GO:0005515 Interacting selectively and non-covalently with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules). | 6 | O48661 (/IPI) O48661 (/IPI) O48661 (/IPI) Q94BN2 (/IPI) Q9ZUB3 (/IPI) Q9ZUB3 (/IPI) | 
| Spermidine synthase activity GO:0004766 Catalysis of the reaction: S-adenosylmethioninamine + putrescine = 5'-methylthioadenosine + spermidine. | 4 | F4KJ05 (/IDA) O48661 (/IDA) O48661 (/IDA) O48661 (/IDA) | 
| Spermidine synthase activity GO:0004766 Catalysis of the reaction: S-adenosylmethioninamine + putrescine = 5'-methylthioadenosine + spermidine. | 1 | F4KJ05 (/ISS) | 
| Spermine synthase activity GO:0016768 Catalysis of the reaction: S-adenosylmethioninamine + spermidine = 5'-methylthioadenosine + spermine. | 1 | F4KJ05 (/IDA) | 
| Spermine synthase activity GO:0016768 Catalysis of the reaction: S-adenosylmethioninamine + spermidine = 5'-methylthioadenosine + spermine. | 1 | F4KJ05 (/IMP) | 
There are 4 GO terms relating to "biological process"
			The search results have been sorted with the annotations that are found most frequently at the top of the
			list. The results can be filtered by typing text into the search box at the top of the table.
			
			
	| GO Term | Annotations | Evidence | 
|---|---|---|
| Spermidine biosynthetic process GO:0008295 The chemical reactions and pathways resulting in the formation of spermidine, N-(3-aminopropyl)-1,4-diaminobutane. | 3 | O48661 (/IDA) O48661 (/IDA) O48661 (/IDA) | 
| Polyamine biosynthetic process GO:0006596 The chemical reactions and pathways resulting in the formation of polyamines, any organic compound containing two or more amino groups. | 1 | F4KJ05 (/IDA) | 
| Spermine biosynthetic process GO:0006597 The chemical reactions and pathways resulting in the formation of spermine, a polybasic amine found in human sperm, in ribosomes and in some viruses and involved in nucleic acid packaging. | 1 | F4KJ05 (/IMP) | 
| Defense response to bacterium GO:0042742 Reactions triggered in response to the presence of a bacterium that act to protect the cell or organism. | 1 | F4KJ05 (/IMP) | 
There are 2 GO terms relating to "cellular component"
			The search results have been sorted with the annotations that are found most frequently at the top of the
			list. The results can be filtered by typing text into the search box at the top of the table.
			
			
	| GO Term | Annotations | Evidence | 
|---|---|---|
| Plasma membrane GO:0005886 The membrane surrounding a cell that separates the cell from its external environment. It consists of a phospholipid bilayer and associated proteins. | 3 | O48661 (/IDA) O48661 (/IDA) O48661 (/IDA) | 
| Cytoplasm GO:0005737 All of the contents of a cell excluding the plasma membrane and nucleus, but including other subcellular structures. | 1 | F4KJ05 (/TAS) | 
