molecules, resulting in the formation of a polyprenyl diphosphate (also known as dehydrodolichyl diphosphate). This subsequently undergoes loss of both phosphate groups, resulting in a polyprenol (dehydrodolichol). Lastly, the α isoprenoid unit is saturated by α-saturase (still a hypothetical enzyme), and this α-saturated polyprenyl alcohol is known as dolichol. Other Dolichols are found in eukaryotes and in archaea, although similar polyprenols molecules are found in bacteria. Polyprenols in bacteria do not contain an α-saturated isoprenoid and are typically smaller in terms of isoprenoid units or carbon length. Polyprenols perform similar functions within bacteria; that is, they function as glycosyl carrier lipids involved in formation of complex branched polysaccharide. However, the cellular process they are involved in is not glycosylation, but instead cell wall biosynthesis. Statins decrease dolichol levels in the body. Medical significance The Australian pharmaceutical company Solagran has been investigating the medical significance of polyprenols and their substitution with dolichols when ingested where there is a deficiency. Trials of Ropren (already pharmaceutically registered as a hepatoprotector) in relation to neurodegenerative diseases (including Alzheimer's disease) in both Russia and Australia indicate considerable potential as a safe and effective treatment. See also Dolichol kinase Polyprenols Solagran Mevalonate inhibition#Dolichol Inhibition References External links Overview at Birkbeck, University of London Cell biology Alkene derivatives Primary alcohols Fatty alcohols Terpenes and terpenoids