Putrescine is an organic compound with the formula (CH2)4(NH2)2. It is a colorless solid that melts near room temperature. It is classified as a diamine. Together with cadaverine, it is largely responsible for the foul odor of putrefying flesh, but also contributes to other unpleasant odors.
Spermine is a polyamine involved in cellular metabolism that is found in all eukaryotic cells. The precursor for synthesis of spermine is the amino acid ornithine. It is an essential growth factor in some bacteria as well. It is found as a polycation at physiological pH. Spermine is associated with nucleic acids and is thought to stabilize helical structure, particularly in viruses.
Spermidine is a polyamine compound found in ribosomes and living tissues and having various metabolic functions within organisms. It was originally isolated from semen.
Spermidine synthase is an enzyme that catalyzes the transfer of the propylamine group from S-adenosylmethioninamine to putrescine in the biosynthesis of spermidine. The systematic name is S-adenosyl 3-(methylthio)propylamine:putrescine 3-aminopropyltransferase and it belongs to the group of aminopropyl transferases. It does not need any cofactors. Most spermidine synthases exist in solution as dimers.
The enzyme adenosylmethionine decarboxylase catalyzes the conversion of S-adenosyl methionine to S-adenosylmethioninamine. Polyamines such as spermidine and spermine are essential for cellular growth under most conditions, being implicated in many cellular processes including DNA, RNA and protein synthesis. S-adenosylmethionine decarboxylase (AdoMetDC) plays an essential regulatory role in the polyamine biosynthetic pathway by generating the n-propylamine residue required for the synthesis of spermidine and spermine from putrescein. Unlike many amino acid decarboxylases AdoMetDC uses a covalently bound pyruvate residue as a cofactor rather than the more common pyridoxal 5'-phosphate. These proteins can be divided into two main groups which show little sequence similarity either to each other, or to other pyruvoyl-dependent amino acid decarboxylases: class I enzymes found in bacteria and archaea, and class II enzymes found in eukaryotes. In both groups the active enzyme is generated by the post-translational autocatalytic cleavage of a precursor protein. This cleavage generates the pyruvate precursor from an internal serine residue and results in the formation of two non-identical subunits termed alpha and beta which form the active enzyme.
Spermine synthase is an enzyme that converts spermidine into spermine. This enzyme catalyses the following chemical reaction
Diamine acetyltransferase 1 is an enzyme that in humans is encoded by the SAT1 gene found on the X chromosome.
Polyamine-modulated factor 1 is a protein that in humans is encoded by the PMF1 gene.
Spermine oxidase is an enzyme that in humans is encoded by the SMOX gene.
Spermine synthase is an enzyme that in humans is encoded by the SMS gene. The protein encoded by this gene belongs to the spermidine/spermine synthases family. This gene encodes a ubiquitous enzyme of polyamine metabolism.
Peroxisomal N(1)-acetyl-spermine/spermidine oxidase is an enzyme that in humans is encoded by the PAOX gene.
Diamine acetyltransferase 2 is an enzyme that in humans is encoded by the SAT2 gene. SAT2 maintains a key metabolic glutamine/glutamate balance underpinning retrograde signaling by dendritic release of the neurotransmitter glutamate.
A polyamine is an organic compound having more than two amino groups. Alkyl polyamines occur naturally, but some are synthetic. Alkylpolyamines are colorless, hygroscopic, and water soluble. Near neutral pH, they exist as the ammonium derivatives. Most aromatic polyamines are crystalline solids at room temperature.
Spermine oxidase (EC 1.5.3.16, PAOh1/SMO, AtPAO1, AtPAO4, SMO) is an enzyme with systematic name spermidine:oxygen oxidoreductase (spermidine-forming). This enzyme catalyses the following chemical reaction
Non-specific polyamine oxidase (EC 1.5.3.17, polyamine oxidase, Fms1, AtPAO3) is an enzyme with systematic name polyamine:oxygen oxidoreductase (3-aminopropanal or 3-acetamidopropanal-forming). This enzyme catalyses the following chemical reaction
Thermospermine synthase (EC 2.5.1.79, TSPMS, ACL5 (ACAULIS5), SAC51) is an enzyme with systematic name S-adenosylmethioninamine:spermidine 3-aminopropyltransferase (thermospermine synthesizing). This enzyme catalyses the following chemical reaction
Polyamines (PAs) are small, positively charged, organic molecules that are ubiquitous in all living organisms. These are considered as one of the oldest group of substances known in biochemistry. There are three common types of polyamines, putrescine, spermidine, hermospermine according to structure, universal distribution in all cellular compartments, and presumed involvement in physiological activities. Polyamine is found in all cellular compartments and physiological activities due to their simple structures. The function of polyamine is very diverse in that it performs a key macromolecule to cellular membrane. Because of their essential roles in plant, mutation of polyamines can cause critical damage on plants. Furthermore, some polyamines like putrescine inhibit biosynthetic activities in plants. The activity of polyamines can be categorized to some parts due to its signalling and growing activity.
Snyder–Robinson syndrome (SRS) is an extremely rare inherited genetic disorder characterized by muscular and skeletal abnormalities, varying degrees of intellectual disability, seizures, and slow development.
Herbert Tabor was an American biochemist and physician-scientist who specialized in the function of polyamines and their role in human health and disease. Tabor was a principal investigator at the National Institute of Diabetes and Digestive and Kidney Diseases where he was Chief of the Laboratory of Biochemical Pharmacology. He was the editor-in-chief of the Journal of Biological Chemistry from 1971 to 2010.
BpsA is a single-module non-ribosomal peptide synthase (NRPS) located in the cytoplasm responsible for the process of creating branched-chain polyamines, and producing spermidine and spermine. It has a singular ligand in its structure involved with Fe3+ and PLIP interactions. As seen by its EC number, it is a transferase (2) that transfers an alkyl or aryl group other than methyl groups (5) (2.5.1). BpsA was first discovered in the archaea Methanococcus jannaschii and thermophile Thermococcus kodakarensis and since then has been used in a variety of applications such as being used as a reporter, researching phosphopantetheinyl transferase (PPTase), and for NRPS domain recombination experiments it can be used as a model. Both (hyper)thermophilic bacteria and euryarchaeotal archaea seem to conserve BpsA and orthologs as branches chains polyamines are crucial for survival. There is also a second type of BpsA also known as Blue-pigment indigoidine synthetase that produces the pigment indigoidine and is found in organisms like Erwinia chrysanthemi. However, not much seems to be known about this variant except that it is a synthase, and it does not yet appear to be classified under an EC number.
