passages.id: split_4_test_1424_passage
passages.type: progene_text
passages.text: In this hypothetical process , trans-2 , trans - 4 - dienoyl - CoA metabolites are generated by Delta ( 3 ) - Delta ( 2 ) - enoyl - CoA isomerase and Delta ( 3 , 5 ) - Delta ( 2 , 4 ) - dienoyl - CoA isomerase and are degraded by 2 - enoyl - CoA hydratase 1 in the absence of 2 , 4 - dienoyl - CoA reductase .