On Physical Properties of Tetraether Lipid Membranes: Effects of Cyclopentane Rings

Department of Biochemistry, Temple University School of Medicine, 3420 North Broad Street, Philadelphia, PA 19140, USA.
Archaea (Impact Factor: 2.71). 09/2012; 2012(11):138439. DOI: 10.1155/2012/138439
Source: PubMed


This paper reviews the recent findings related to the physical properties of tetraether lipid membranes, with special attention to the effects of the number, position, and configuration of cyclopentane rings on membrane properties. We discuss the findings obtained from liposomes and monolayers, composed of naturally occurring archaeal tetraether lipids and synthetic tetraethers as well as the results from computer simulations. It appears that the number, position, and stereochemistry of cyclopentane rings in the dibiphytanyl chains of tetraether lipids have significant influence on packing tightness, lipid conformation, membrane thickness and organization, and headgroup hydration/orientation.

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    • "Arrangement of the TEL membrane with the caldarchaeol ring structures with no pentacycles (a, NPC), three (b, TPC) and five pentacycles (c, FPC) (Chong et al. [33]). "

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    • "The lipid membrane plays a fundamental role in energy conservation and the maintenance of intercellular homeostasis. Microorganisms synthesize diverse lipid structures with widely varying biophysical properties (Koga and Morii, 2007; Chong et al., 2012) that have facilitated their diversification into environments with wide ranging conditions, including extremes of temperature and pH (Macalady et al., 2004; Pearson et al., 2008; Boyd et al., 2013). The predominant membrane lipids of Archaea are isoprenoid glycerol dialkyl glycerol tetraethers (iGDGTs), which occur ubiquitously in the natural environment (Schouten et al., 2000, 2013). "
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