Spermine

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. It functions as an intracellular free radical scavenger to protect DNA from free radical attack. Spermine is the chemical primarily responsible for the characteristic odor of semen. Antonie van Leeuwenhoek first described crystals of spermine phosphate in human semen in 1678. The name spermin was first used by the German chemists Ladenburg and Abel in 1888, and the correct structure of spermine was established in the 1920s, independently by Dudley, Rosenheim, and Starling in England and by Wrede et al. in Germany.