title: Novel ether lipid cardiolipins in archaeal membranes of extreme haloalkaliphiles.
abstract: The lipidome of two extremely haloalkaliphilic archaea, Natronococcus occultus and Natronococcus amylolyticus, has been examined by means of combined thin-layer chromatography and MALDI-TOF/MS analyses. The detailed investigation of lipid profiles has confirmed the presence of i) ether lipid phosphatidylglycerol and phosphatidylglycerophosphate methyl ester as main lipid components, ii) both C(20) and C(25) isopranoid chains in the lipid core and yielded new findings on membrane lipids of these unusual organisms. Besides some novel minor or trace phospholipids and glycolipids, data indicate the presence of ether lipid cardiolipin variants constituted by different combinations of C(20) and C(25) isopranoid chains, never before described in archaea. The role of C(25) isopranoid chains in the adaptation to high pH gradients in the presence of very high salt concentrations is discussed.
authors.affiliation: Department of Basic Medical Sciences, University of Bari Aldo Moro, 70124 Bari, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Angelini
authors.forename: Paulina
authors.initials: P
authors.lastname: Corral
authors.forename: Patrizia
authors.initials: P
authors.lastname: Lopalco
authors.forename: Antonio
authors.initials: A
authors.lastname: Ventosa
authors.forename: Angela
authors.initials: A
authors.lastname: Corcelli
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D002308:Cardiolipins / Q000737:chemistry / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D019634:Natronococcus / Q000737:chemistry / Q000378:metabolism; D010742:Phospholipid Ethers / Q000737:chemistry / Q000378:metabolism
chemical_list: D002308:Cardiolipins; D010742:Phospholipid Ethers