title: Glycerol monoalkanediol diethers: a novel series of archaeal lipids detected in hydrothermal environments.
abstract: BACKGROUND
  Recent advances in analytical techniques used to study archaeal membrane lipids have led to the identification of several novel di- and tetraether lipid structures. Here, we report the presence of a previously unknown series of archaeal diethers that have been detected exclusively in hydrothermally affected environments.
  
  
  METHODS
  Polar lipid extracts were analyzed using high-performance liquid chromatography coupled to positive ion atmospheric pressure chemical ionization mass spectrometry (HPLC/APCI-MS). Identification of the novel archaeal diethers was achieved using a triple quadrupole mass spectrometer operated in MS/MS mode and by comparison of characteristic retention time patterns.
  
  
  RESULTS
  Modern and fossil sediments deposited under hydrothermal conditions contained variable abundances of archaeal lipids including archaeol, glycerol trialkyl glycerol tetraether (GTGT-0), isoprenoid glycerol dialkyl glycerol tetraethers (GDGTs), glycerol monoalkyl glycerol tetraethers (GMGTs) and glycerol dialkanol diethers (GDDs). In addition to these well-established archaeal lipids, we detected a novel series of archaeal diethers (i.e., glycerol monoalkanediol diethers (GMDs)) that are structurally related to GMGTs but which lack one terminal glycerol moiety and contain 0-2 cyclopentyl ring systems.
  
  
  CONCLUSIONS
  The unique presence of GMDs in hydrothermally affected environments suggests that these compounds may constitute an exclusive and yet unknown component of the cell wall membrane of (hyper)thermophilic Archaea. The presented mass spectral characteristics will facilitate detection of these components in pure cultures of Archaea and natural environments.
authors.affiliation: Christian-Albrechts-University, Institute of Geosciences, Department of Organic Geochemistry, Ludewig-Meyn-Straße 10, 24118, Kiel, Germany.
authors.forename: Thorsten
authors.initials: T
authors.lastname: Bauersachs
authors.affiliation: Christian-Albrechts-University, Institute of Geosciences, Department of Organic Geochemistry, Ludewig-Meyn-Straße 10, 24118, Kiel, Germany.|Curtin University, WA-OIGC, Department of Chemistry, 6845, Perth, Australia.
authors.forename: Lorenz
authors.initials: L
authors.lastname: Schwark
mesh_terms: D001105:Archaea / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D005580:Fossils; D019015:Geologic Sediments / Q000737:chemistry; D020404:Glycerophospholipids / Q000032:analysis / Q000737:chemistry*; D005995:Glyceryl Ethers / Q000032:analysis / Q000737:chemistry*; D060086:Hydrothermal Vents / Q000382:microbiology; D008563:Membrane Lipids / Q000032:analysis / Q000737:chemistry*; D053719:Tandem Mass Spectrometry
chemical_list: D020404:Glycerophospholipids; D005995:Glyceryl Ethers; D008563:Membrane Lipids