Caldarchaeol is a membrane-spanning

lipid Lipids are a broad group of naturally-occurring molecules which includes fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The functions of lipids include ...

found in

hyperthermophilic A hyperthermophile is an organism that thrives in extremely hot environments—from 60 °C (140 °F) upwards. An optimal temperature for the existence of hyperthermophiles is often above 80 °C (176 °F). Hyperthermophiles are often within the doma ...

archaea Archaea ( ; singular archaeon ) is a domain of single-celled organisms. These microorganisms lack cell nuclei and are therefore prokaryotes. Archaea were initially classified as bacteria, receiving the name archaebacteria (in the Archaebac ...

. Membranes made up of caldarchaeol are more stable since the hydrophobic chains are linked together, allowing the microorganisms to withstand high temperatures. It is also known as dibiphytanyldiglycerol tetraether. Two

glycerol Glycerol (), also called glycerine in British English and glycerin in American English, is a simple triol compound. It is a colorless, odorless, viscous liquid that is sweet-tasting and non-toxic. The glycerol backbone is found in lipids known ...

units are linked together by two strains which consist of two

phytane Phytane is the isoprenoid alkane formed when phytol, a constituent of chlorophyll, loses its hydroxyl group. When phytol loses one carbon atom, it yields pristane. Other sources of phytane and pristane have also been proposed than phytol. Prista ...

s linked together to form a linear chain of 32 carbon atoms (40 carbons including methyl sidechains). The

configuration Configuration or configurations may refer to: Computing * Computer configuration or system configuration * Configuration file, a software file used to configure the initial settings for a computer program * Configurator, also known as choice board ...

of the macrocyclic tetraether has been determined by total synthesis of the C40-diol and comparison with a sample of obtained by degradation of natural tetraether. A synthesis of tetraether has also been carried out.

Notes

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Additional references

Focus of research
University of Occupational and Environmental Health, Kitakyushu, Japan * Langworthy TA, ''Biochim Biophys Acta'' 1977, 487, 37 * Monolayer properties of archaeol and caldarchaeol polar lipids of a methanogenic archaebacterium, Methanospirillum hungatei, at the air/water interface. Tomoaia-Cotisel M, Chifu E, Zsako J, Mocanu A, Quinn PJ, Kates M. ''Chem Phys Lipids''. 1992 Nov;63(1-2):131-8 * Ether polar lipids of methanogenic bacteria: structures, comparative aspects, and biosyntheses. Koga Y, Nishihara M, Morii H, Akagawa-Matsushita M. ''Microbiol Rev''. 1993 Mar;57(1):164-82. Lipids Macrocycles