Phosphate Esters in Goat Placenta

the chromatograms, therefore, are likely to be minimal. Evidence that ethanolamine was liberated by the action of phosphomonoesterase was obtained by paper chromatography of the dinitrophenyl derivatives prepared from the hydrolysate. Only one derivative appeared in the hydrolysate but not in the control and it behaved just like pure dinitrophenylethanolamine in the butanol-water system of Mellon et al. (1953). Dinitrophenylserine was absent from both preparations. Electrophoreai8. Electrophoresis (barbitone buffer, pH 8-6, I 0 05, 0 4 mA/cm. width, Whatman no. 4 paper) of fraction A prepared as above from goat placenta revealed the presence of a phosphoric acid ester fraction that moved towards the anode at a rate of about 0-46 relative to inorganic orthophosphate (10). Most ofthe phosphorus-containing material in fraction B moved at the same rate as did a mixture ofphosphorylethanolamine and phosphorylcholine under the same conditions. Determination of the total phosphorus on the paper after electrophoresis showed that 59 1 % of the total phosphorus present in fractionA from goat placenta was present in the region ofrelative rate 0-46. Since fraction B accounts for 71'4% of the total phosphorus in fraction A, and phosphorylcholine and phosphorylethanolamine account for 80-3% of the total phosphorus in fraction B, the two esters account for 57*4% of the total phosphorus in fraction A. This figure is compatible with that obtained by quantitative electrophoresis described above.