Arsoniumphospholipid in algae

Abstract
A novel phospholipid containing Ar was formed by all marine algae cultured in [74As]arsenate. Components of the labeled algal [Chaetoceros concavicornis] extracts readily separated by 2-dimensional paper radiochromatography. Base-catalyzed deacylation of the major lipid yielded a phosphodiester identical to 1 of the 2 major water-soluble compounds. Acid or enzymic hydrolysis of the phosphodiester produced a product identified as trimethylarsoniumlactic acid. The structure of the phospholipid therefore is O-phosphatidyltrimethylarsoniumlactic acid. Detoxication of arsenate by marine algae leads to accumulation of the arsoniumphospholipid as a major reservoir for arsenic. Its degradation to trimethylarsoniumbetaine, dimethylarsinic acid, methanearsonic acid and arsenate in marine food chains and its metabolism in human beings are of considerable interest.