OCCURRENCE OF THE O-PHOSPHODIESTER OF l-SERINE AND ETHANOLAMINE IN TURTLE TISSUE

Numerous two-dimensional paper chromatograms made of tissues of the developing chick embryo and of several strains of mice during prenatal and postnatal development1 revealed that the spot presumed to be ethanolamine O-phosphoric acid (EP) decreased rapidly with age (see references (l-6) for studies of EP and glycerylphosphorylethanolamine (GPE) in mammalian tissues). It was conjectured that the rate of decrease of EP might be slower in species possessing a longer life span and that tissues from such animals might furnish a more suitable material for further study of the possible relationships of EP with other cellular constituents. As expected, alcoholic extracts of tissues of young alligator and turtle revealed much larger amounts of a ninhydrin-reactive material behaving like EP on conventional paper chromatograms than had been noted previously in extracts from any other species. However, further study revealed that the chief component of the chromatographic spot was not EP. The present communication describes the isolation and characterization of the substance as the 0-phosphodiester of L-serine and ethanolamine.