passages.id: split_1_test_2778_passage
passages.type: progene_text
passages.text: In experiments in which the homologous enzyme , 3-deoxy-D-arabino-heptulosonate 7-phosphate ( DAH7-P ) synthase was incubated with D,L-glyceraldehyde 3-phosphate ( G3P ) and [2,3-(13)C(2)]-PEP , pyruvate and phosphate were the predominant species formed , suggesting that the reaction catalyzed by DAH7-P synthase starts with a nucleophilic attack by water onto PEP as observed in E. coli KDO8-P synthase .