IDENTIFICATION OF DEGRADATION ARTIFACTS FORMED UPON TREATMENT OF HYDROXYDIETHER LIPIDS FROM METHANOGENS WITH METHANOLIC HCL

Treatment of purified 3-hydroxydiether lipid from Methanosarcina barkeri by standard conditions for head-group removal (2.5% methanolic HCl, 70-degrees-C) resulted in conversion to six identifiable degradation products. The four most abundant products were identified by mass spectrometry and nuclear magnetic resonance as monophytanylglycerol, 3-methoxydiether, and cis-trans isomers of a diether unsaturated between carbons 3 and 4. The latter lipid products may be mistaken for 2,3-di-O-phytanyl-sn-glycerol (standard diether) and 2-O-sesterterpanyl-3-O-phytanyl-sn-glycerol when separated by thin-layer chromatography.