Lipid biomolecules in silica sinters: indicators of microbial biodiversity.

To explore further the diversity of the microorganisms and their relationship with geothermal sinters, we examined the lipids preserved in six sinters associated with four different hot spring (58-82 degrees C) areas of the Taupo Volcanic Zone (TVZ), New Zealand. These sinters contain microbial remains, but the process of mineralization has rendered them largely unidentifiable. Dominant lipids include free fatty acids, 1,2-diacylglycerophospholipids, 1,2-di-O-alkylglycerols, glycerol dialkylglycerol tetraethers and 1-O-alkylglycerols.