passages.id: split_1_test_1913_passage
passages.type: progene_text
passages.text: Our results suggest that in the fruit fly GDP-fucose , the donor for fucosyltransferase reactions , is formed exclusively via the de novo pathway from GDP-mannose through enzymatic reactions catalyzed by GDP-D-mannose 4,6-dehydratase ( GMD ) and GDP-4-keto-6-deoxy-D-mannose 3,5-epimerase/4-reductase ( GMER , also known as FX in man ) .