Evidence for indirect utilization of glycine for production of N-bases of glycerophospholipids and sphingolipids in mouse neuroblastoma cells by using 15N-labeled glycine.

After mouse neuroblastoma cells were cultured with [15N]glycine in Dulbecco's modified Eagle's medium for total four days, they gave significant amounts of 15N-atom% excess in phosphatidylserine, phosphatidylethanolamine, ethanolamine plasmalogen, phosphatidylcholine, sphingomyelin and ceramide. These results were compared with those of [15N]choline, [15N]ethanolamine and [15N]DL-serine used in place of [15N]glycine for the experiments. It was suggested that [15N]glycine is taken into the cells and metabolically converted to [15N]L-serine, which is well known to be used for the production of polar head groups of glycerophospholipids and sphingosine.