Taxol Biosynthesis: Differential Transformations of Taxadien-5α-ol and Its Acetate Ester by Cytochrome P450 Hydroxylases from Taxus Suspension Cells
作者:Alenka Lovy Wheeler、Robert M Long、Raymond E.B Ketchum、Christopher D Rithner、Robert M Williams、Rodney Croteau
DOI:10.1006/abbi.2001.2377
日期:2001.6
rearrangement) of this olefin precursor to taxa-4(20),11(12)-dien-5 alpha-ol, and further oxygenation and acylation reactions. Based on the abundances of naturally occurring taxoids, the subsequent order of oxygenation of the taxane core is considered to occur at C10, then C2 and C9, followed by C13, and finally C7 and C1. Circumstantial evidence suggests that the acetylation of taxadien-5 alpha-ol
红豆杉物种中的二萜类抗肿瘤药紫杉醇的生物合成涉及将普遍存在的类异戊二烯中间体香叶基香叶基二磷酸环化成紫杉类4(5),11(12)-二烯,然后通过细胞色素P450介导的该烯烃的羟基化(烯丙基重排)分类单元4(20),11(12)-dien-5α-ol的前体,以及进一步的氧化和酰化反应。基于大量天然存在的类紫杉醇,认为紫杉烷核的后续氧化顺序发生在C10,然后是C2和C9,然后是C13,最后是C7和C1。间接证据表明,紫杉二烯-5α-醇的乙酰化可能构成紫杉醇生物合成的第三个特定步骤。为了确定紫杉醇或相应的乙酸酯是否充当后续氧化反应的直接前体,将从诱导的紫杉细胞中分离并针对细胞色素P450催化进行了优化的微粒体制剂与每种潜在的底物一起孵育。通过微粒体制剂的细胞色素P450酶,以可比的速率将紫杉二烯醇和乙酸紫杉二烯乙酸酯两者氧化至二醇水平和高级多元醇水平。制备规模的孵育可分离出足够量的紫杉烯醇衍生的