嘧啶核苷酸 磷酸酶 嘧啶核苷 核苷酶嘧啶 O NH; NADPH+H'NADP CH HN CH HN CH, 0( CH, N H 胞嘧啶 ,0 尿嘧啶 CO,+NH; H20 H B-丙氨酸 H, CH. HN-CH,-CH,-COOH CH, H