Glycerol dibiphytanyl glycerol tetraethers (GDGTs) are large cyclic tetraether molecules biosynthesized by archaebacteria as membrane building blocks, spanning the membrane lipid layer. Examples of GDGTs are caldarchaeol and crenarchaeol. The latter contains four cyclopentane and one cyclohexane ring within the “large-ring backbone” (see reference [1] and Crenarchaeol, derived from Crenarchaea). The use of biphytanyl glycerol diethers and GDGTs distinguish archaea from other bacteria and eukaryotes. Archaea live in extreme environments and the ether linkages, which are more stable than the ester linkages in membrane lipids of non-archaea, have been interpreted as an adaption to thrive or survive under extreme conditions.
The notation GDGT-n, in which n is an integer specifying the total number of cyclopentane rings in a GDGT molecules, has been introduced [1,2]. Caldarchaeol is a GDGT-0 and crenarchaeol a GDGT-4 compound.
Keywords: biochemistry, thermophilic organisms, pelagic crenarchaeota, membrane architecture
References
[1] J. S. Sinninghe Damsté, S. Schouten, E. C. Hopmans, A. C. T. Duin and J. A. J. Geenevasen: Crenarchaeol: the characteristic core glycerol dibiphytanyl glycerol tetraether membrane lipid of cosmopolitan pelagic crenarchaeots. J. Lipid Res. 2002, 43, pp. 1641-1651.
DOI: 10.1194/jlr.M200148-JLR200.
[2] J. S. Sinninghe Damsté, W. I. C. Rijpstra, E. C. Hopmans, F. G. Prahl, S. G. Wakeham and S. Schouten: Distribution of Membrane Lipids of Planktonic Crenarchaeota in the Arabian Sea. Appl. Env. Microbiol. 2002, 68, pp. 2997-3002.
DOI: 10.1128/AEM.68.6.2997-3002.2002.
Monday, October 26, 2009
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