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Cold Adaptation in the Antarctic Archaeon, Methanococcoides burtonii, Involves Membrane Lipid Unsaturation

Citation

Nichols, DS and Miller, MR and Davies, NW and Goodchild, A and Raftery, M and Cavicchioli, R, Cold Adaptation in the Antarctic Archaeon, Methanococcoides burtonii, Involves Membrane Lipid Unsaturation, Journal of Bacteriology, 186, (24) pp. 8508-8515. ISSN 0021-9193 (2004) [Refereed Article]

DOI: doi:10.1128/JB.186.24.8508-8515.2004

Abstract

Direct analysis of membrane lipids by liquid chromatography-electrospray mass spectrometry was used to demonstrate the role of unsaturation in ether lipids in the adaptation of Methanococcoides burtonii to low temperature. A proteomics approach using two-dimensional liquid chromatography-mass spectrometry was used to identify enzymes involved in lipid biosynthesis, and a pathway for lipid biosynthesis was reconstructed from the M. burtonii draft genome sequence. The major phospholipids were archaeol phosphatidylglycerol, archaeol phosphatidylinositol, hydroxyarchaeol phosphatidylglycerol, and hydroxyarchaeol phosphatidylinositol. All phospholipid classes contained a series of unsaturated analogues, with the degree of unsaturation dependent on phospholipid class. The proportion of unsaturated lipids from cells grown at 4°C was significantly higher than for cells grown at 23°C. 3-Hydroxy-3-methylglutaryl coenzyme A synthase, farnesyl diphosphate synthase, and geranylgeranyl diphosphate synthase were identified in the expressed proteome, and most genes involved in the mevalonate pathway and processes leading to the formation of phosphatidylinositol and phosphatidylglycerol were identified in the genome sequence. In addition, M. burtonii encodes CDP-inositol and CDP-glycerol transferases and a number of homologs of the plant geranylgeranyl reductase. It therefore appears that the unsaturation of lipids may be due to incomplete reduction of an archaeol precursor rather than to a desaturase mechanism. This study shows that cold adaptation in M. burtonii involves specific changes in membrane lipid unsaturation. It also demonstrates that global methods of analysis for lipids and proteomics linked to a draft genome sequence can be effectively combined to infer specific mechanisms of key biological processes.

Item Details

Item Type:Refereed Article
Research Division:Biological Sciences
Research Group:Biochemistry and Cell Biology
Research Field:Analytical Biochemistry
Objective Division:Environment
Objective Group:Land and Water Management
Objective Field:Antarctic and Sub-Antarctic Land and Water Management
Author:Nichols, DS (Dr David Nichols)
Author:Miller, MR (Dr Matthew Miller)
Author:Davies, NW (Associate Professor Noel Davies)
ID Code:29351
Year Published:2004
Web of Science® Times Cited:69
Deposited By:Agricultural Science
Deposited On:2004-08-01
Last Modified:2005-06-03
Downloads:0

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