passages.id: split_1_test_3341_passage
passages.type: progene_text
passages.text: In animal tissues , NAPE is formed by transfer of a fatty acyl chain at the sn - 1 position of glycerophospholipids to the amino group of phosphatidylethanolamine ( PE ) , and this reaction is believed to be the principal rate - limiting step in N - acylethanolamine synthesis .