Biosynthesis of Ether-Type Polar Lipids in Archaea and Evolutionary Considerations

Department of Chemistry, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan.
Microbiology and Molecular Biology Reviews (Impact Factor: 14.61). 04/2007; 71(1):97-120. DOI: 10.1128/MMBR.00033-06
Source: PubMed


This review deals with the in vitro biosynthesis of the characteristics of polar lipids in archaea along with preceding in vivo studies. Isoprenoid chains are synthesized through the classical mevalonate pathway, as in eucarya, with minor modifications in some archaeal species. Most enzymes involved in the pathway have been identified enzymatically and/or genomically. Three of the relevant enzymes are found in enzyme families different from the known enzymes. The order of reactions in the phospholipid synthesis pathway (glycerophosphate backbone formation, linking of glycerophosphate with two radyl chains, activation by CDP, and attachment of common polar head groups) is analogous to that of bacteria. sn-Glycerol-1-phosphate dehydrogenase is responsible for the formation of the sn-glycerol-1-phosphate backbone of phospholipids in all archaea. After the formation of two ether bonds, CDP-archaeol acts as a common precursor of various archaeal phospholipid syntheses. Various phospholipid-synthesizing enzymes from archaea and bacteria belong to the same large CDP-alcohol phosphatidyltransferase family. In short, the first halves of the phospholipid synthesis pathways play a role in synthesis of the characteristic structures of archaeal and bacterial phospholipids, respectively. In the second halves of the pathways, the polar head group-attaching reactions and enzymes are homologous in both domains. These are regarded as revealing the hybrid nature of phospholipid biosynthesis. Precells proposed by Wächtershäuser are differentiated into archaea and bacteria by spontaneous segregation of enantiomeric phospholipid membranes (with sn-glycerol-1-phosphate and sn-glycerol-3-phosphate backbones) and the fusion and fission of precells. Considering the nature of the phospholipid synthesis pathways, we here propose that common phospholipid polar head groups were present in precells before the differentiation into archaea and bacteria.

Download full-text


Available from: Hiroyuki Morii
    • "Archaea represent a domain of life with good adoptability to survive in hostile environments such as hot springs. Archaeal membrane lipids consist of the core structures dialkyl glycerol diether (DGD) and/or glycerol-dialkyl-glycerol tetraether (GDGT) wherein fully saturated phytanyl chains (20 or 40 carbons in length, respectively), are linked via ether bonds to the glycerol backbone(s) (De Rosa et al., 1986; Koga and Morii, 2007). While DGD-lipids form bilayer structures similar to conventional "
    [Show abstract] [Hide abstract]
    ABSTRACT: In an attempt to design an oral drug delivery system, suited to protect labile drug compounds like peptides and proteins against the harsh environment in the stomach and upper intestine, we have prepared liposomes from phospholipids, cholesterol and archaeal lipids. As source for the archaeal lipids we used Sulfolobus islandicus, a hyperthermophilic archaeon, whose lipids have not been used in liposomes before. Culturing conditions and extraction protocols for its membrane lipids were established and the lipid composition of the crude lipid extract was characterized. The extracted membrane lipid fraction of S. islandicus consisted primarily of diether lipids with only a small fraction of tetraether lipids. Small unilamellar liposomes with 18% (mole/mole) of crude archaeal lipid extract were from S.islandicus were produced, for the first time and proven to be stabilized against aggressive bile salts as determined by loss of entrapped marker (calcein). At 4.4mM taurocholate (physiological taurocholate level) liposomes containing archaeal lipids retained entrapped marker better than liposomes made of egg phosphatidylcholine (PC) alone and to an extent similar to liposomes made of egg PC and cholesterol. Our findings showed that crude archaeal lipid extracts have, to a certain extent, stabilizing effects on liposomes similar to purified tetraether lipid fractions tested previously. Copyright © 2015. Published by Elsevier B.V.
    No preview · Article · Jul 2015 · International Journal of Pharmaceutics
  • Source
    • "Interestingly , several versions of this pathway have been observed in eukaryotes: whilst in Kinetoplastid and Apicomplexan organisms both enzymes are phospholipases D, in plants both enzymes are CDP transferases . Moreover, recent evidence in silico has demonstrated the presence of a bacterial-like phosphatidylglycerol phosphate synthase together with evidence of CL in several species of archaeas [8] [9] [10]. This intricate diversity of pathways for CL biosynthesis has been poorly studied; the only study was restricted to uncovering the evolution of Cls and CL-remodeling enzymes (a process restricted to the Eukarya Biochimica et Biophysica Acta 1847 (2015) 599–606 "

    Full-text · Article · Apr 2015 · Biochimica et Biophysica Acta (BBA) - Bioenergetics
  • Source
    • "The proposed biosynthetic route to GDGTs for archaea involves the dimerisation of phosphate-modified GDDs (Koga and Morii, 2007 and references therein; Scheme 2), with GTGTs believed to accumulate when macrocyclisation does not proceed to completion (de la Torre et al., 2008). Structural evidence suggests that cyclopentyl ring incorporation steps, and the biphytane cross-linking steps which lead to GMGTs, occur after formation of precursor GDDs (De Rosa et al., 1983b; de la Torre et al., 2008; Schouten et al., 2008a; Knappy et al., 2011). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Lipid extracts from several aquatic sediments and a compost-fertilised soil contained higher homologues of widely reported archaeal diglycerol tetraether cores. Liquid chromatography-tandem mass spectrometry indicated that the structures are based on polyols not reported in archaeal membrane lipids, homoglycerol (GH; C4H8O3) or dihomoglycerol (GDH; C5H10O3) groups, which replace one of the terminal glycerol (C3H6O3) moieties in the diglycerol lipids. The homologues included monoalkyl, dialkyl and trialkyl tetraether cores, some of which were inferred to contain cyclopentyl rings. Distributional differences between diglycerol tetraethers and associated homologues in all the samples indicate a biogenic route and not a diagenetic route to the latter. The homologues could be prominent components of tetraether distributions in some samples (up to ca. 22% of isoprenoid tetraether lipid cores), are preserved in ancient sediments (e.g. Jurassic shales, 160 Ma) and occur in disparate terrestrial and oceanic settings. Hence, their presence in other sedimentary archives would be expected. The components clearly encode different information from the diglycerol tetraethers and may allow refinement of interpretations from environmental ether lipid distributions.
    Full-text · Article · Nov 2014 · Organic Geochemistry
Show more