Variability of lipid constituents of the soil cyanobacterium Microcoleus vaginatus from the Dead Sea Basin and Negev Desert

A study of lipids of the soil cyanobacterium Microcoleus vaginatus, which w as isolated from microbial crusts collected in the Dead Sea basin and in th e Negev desert, was performed. Twenty-six hydrocarbons and fatty acids were separated and identified by GC/MS using serially coupled capillary columns of different polarity. Changes in the lipid composition were evaluated by comparison of samples collected from different locations. Heptadecane, 1-he ptadecene, 6- and 7-methylheptadecane, hexadecanoic and 9(Z)-octadecenoic a cids were identified as the major constituents. Biochemical mechanisms of p roduction of the different lipid compounds under UV irradiation are propose d.