Spermidine synthase
Encyclopedia
Spermidine synthase is an enzyme
that catalyzes the transfer
of the propylamine group from S-adenosylmethioninamine
to putrescine
in the biosynthesis of spermidine
. The enzyme has a molecular weight of approximately 73,000 kD and is composed of two subunits of equal size.
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
that catalyzes the transfer
Transferase
In biochemistry, a transferase is an enzyme that catalyzes the transfer of a functional group from one molecule to another . For example, an enzyme that catalyzed this reaction would be a transferase:In this example, A would be the donor, and B would be the acceptor...
of the propylamine group from S-adenosylmethioninamine
S-Adenosylmethioninamine
S-Adenosylmethioninamine is a substrate that is involved in the biosynthesis of polyamines including spermidine, spermine, and thermospermine.- See also :* ACAULIS5* Adenosylmethionine decarboxylase...
to putrescine
Putrescine
Putrescine is a foul-smelling organic chemical compound NH24NH2 that is related to cadaverine; both are produced by the breakdown of amino acids in living and dead organisms and both are toxic in large doses...
in the biosynthesis of spermidine
Spermidine
Spermidine is a polyamine involved in cellular metabolism. Its known actions include:#Inhibition of neuronal nitric oxide synthase, nNOS#Assisting the in vitro process of transcribing RNA via stimulation of T4 polynucleotide kinase and T7 RNA polymerase activity; it binds to and precipitates DNA...
. The enzyme has a molecular weight of approximately 73,000 kD and is composed of two subunits of equal size.