目的:紫杉烷13α-羟化酶是紫杉醇下游合成途径关键酶之一,负责催化紫杉二烯-5α-醇的C13侧链发生羟基化反应生成紫杉二烯-5α、13α-二醇。该研究从南方红豆杉中克隆出紫杉烷13α-羟化酶基因并对其序列进行生物信息学分析。方法:利用南方红豆杉的总DNA和总RNA为模板,采用PCR和RT-PCR技术克隆出紫杉烷13α-羟化酶基因的DNA序列和cDNA序列,利用swiss-prot、DNAMAN等生物信息学工具对其核酸序列和蛋白序列进行分析。结果:测序结果显示其cDNA序列长度为1 651bp,含有一个1 458bp的开放阅读框,同源性比较分析结果表明,其氨基酸序列与已经报道的蔓地亚红豆杉的紫杉烷13α-羟化酶氨基酸序列的一致性为96%。结论:成功克隆出南方红豆杉紫杉烷13α-羟化酶基因,为利用合成生物学工程技术生产紫杉醇或其前体物质提供了分子基础。
Objective: Taxane 13α-hydroxylase is one of the six hydroxylases involved in the downstream pathway of Taxol biosynthesis and it catalyzes the C13 side chain of taxa-4(20),11(12)-dien-5alpha-ol to form taxa-4(20),11(12)-dien-5 alpha,13 alpha-diol by hydroxylation reaction.In this study,taxane 13α-hydroxylase gene from Taxus chinensis var.mairei was cloned and its sequence had been analyzed by bioinformatics.Method: Total DNA and RNA from Taxus chinensis var.mairei were used as the template to clone the DNA sequence and cDNA sequence of taxane 13α-hydroxylase gene by PCR and RT-PCR respectively.Bioinformatics softwares were used to analysis the protein sequence.Result: The result of sequencing showed that the length of cDNA is 1651 bp.The gene contained an opening reading frame of 1458 bp,which coded for 485 amino acid residues.The result of alignment showed that its cDNA sequence has 99% similarity to the taxane 13α-hydroxylase gene of Taxus x media which has been reported in NCBI,and its protein sequence has 96% similarity to taxane 13α-hydroxylase of Taxus x media.Conclusion: Taxane 13α-hydroxylase gene from Taxus chinensis var.mairei was obtained,which would provide the molecular base for producing Taxol or its advanced precursors by genetic engineering.