The structural elucidation of the polar lipids in Halobacterium trapan
icum is reported with particular emphasis on a new sulfated disacchari
de derivative of 2,3-di-O-phytanyl-sn-glycerol. The full structural de
signation of this glycolipid is hytanyl-1-O-(mannopyranosyl-(2-sulfate
)-alpha-D-1- 2-glucopyranosyl-alpha-D)-sn-glycerol. The value of glyco
lipid structures in the taxonomy of halophilic Archaea is also discuss
ed.