An enzyme that catalyzes the transfer of the propylamine moiety from 5'-deoxy-5'-S-(3-methylthiopropylamine)sulfonium adenosine to spermidine in the biosynthesis of spermine. It has an acidic isoelectric point at pH 5.0. EC 2.5.1.22.

A biogenic polyamine formed from spermidine. It is found in a wide variety of organisms and tissues and is an essential growth factor in some bacteria. It is found as a polycation at all pH values. Spermine is associated with nucleic acids, particularly in viruses, and is thought to stabilize the helical structure.

An enzyme that catalyzes the transfer of the propylamine moiety from 5'-deoxy-5'-S-(3-methylthiopropylamine)sulfonium adenosine to putrescine in the biosynthesis of spermidine. The enzyme has a molecular weight of approximately 73,000 kDa and is composed of two subunits of equal size.

A polyamine formed from putrescine. It is found in almost all tissues in association with nucleic acids. It is found as a cation at all pH values, and is thought to help stabilize some membranes and nucleic acid structures. It is a precursor of spermine.

Nucleosides in which the base moiety is substituted with one or more sulfur atoms.

Polyamines are organic compounds with more than one amino group, involved in various biological processes such as cell growth, differentiation, and apoptosis, and found to be increased in certain diseases including cancer.

A class of genetic disorders resulting in INTELLECTUAL DISABILITY that is associated either with mutations of GENES located on the X CHROMOSOME or aberrations in the structure of the X chromosome (SEX CHROMOSOME ABERRATIONS).

A family of alicyclic hydrocarbons containing an amine group with the general formula R-C6H10NH2.

An enzyme that catalyzes the decarboxylation of S-adenosyl-L-methionine to yield 5'-deoxy-(5'-),3-aminopropyl-(1), methylsulfonium salt. It is one of the enzymes responsible for the synthesis of spermidine from putrescine. EC 4.1.1.50.

Biogenic amines having more than one amine group. These are long-chain aliphatic compounds that contain multiple amino and/or imino groups. Because of the linear arrangement of positive charge on these molecules, polyamines bind electrostatically to ribosomes, DNA, and RNA.

A toxic diamine formed by putrefaction from the decarboxylation of arginine and ornithine.

Organic chemicals which have two amino groups in an aliphatic chain.

An inhibitor of ORNITHINE DECARBOXYLASE, the rate limiting enzyme of the polyamine biosynthetic pathway.

Transferases are enzymes transferring a group, for example, the methyl group or a glycosyl group, from one compound (generally regarded as donor) to another compound (generally regarded as acceptor). The classification is based on the scheme "donor:acceptor group transferase". (Enzyme Nomenclature, 1992) EC 2.

Adenosine molecules which can be substituted in any position, but are lacking one hydroxyl group in the ribose part of the molecule.

A pyridoxal-phosphate protein, believed to be the rate-limiting compound in the biosynthesis of polyamines. It catalyzes the decarboxylation of ornithine to form putrescine, which is then linked to a propylamine moiety of decarboxylated S-adenosylmethionine to form spermidine.

The removal of a carboxyl group, usually in the form of carbon dioxide, from a chemical compound.

Physiologic methyl radical donor involved in enzymatic transmethylation reactions and present in all living organisms. It possesses anti-inflammatory activity and has been used in treatment of chronic liver disease. (From Merck, 11th ed)