PMC

Structures of thermophilic lipid candidates (a) diphytanylglycerol (archaeol: archaeal diether lipid); (b) cyclic archaeol; (c) digeranylgeranylglycerophosphate (DGGGP); (d) caldarchaeol (archaeal tetraether lipid); (e) cyclopentane-containing caldarchaeol; (f) bacterial dither lipids; (g) 15,16-dimethyl-30-glyceryloxytriacontanoic acid; (h) 1,2-di-hydroxynonadecane (long-chain diol lipid); (i) palmitic acid (saturated straight chain fatty acid); (j) cis-vaccenic acid (monounsaturated straight chain fatty acid); (k) iso-C17 fatty acid; (l) anteiso-C17 fatty acid; (m) 15,16-dimethyltriacontandioic acid (diabolic acid); (n) 11-cyclohexylundecanoic acid. (a)–(e) Archaeal lipids; (f)–(n) bacterial lipids.