中文摘要：

CYP725A4在大肠杆菌等原核宿主中难以实现高效功能表达,是制约紫杉醇异源合成的瓶颈之一.文中利用生物信息学方法对该酶分子的序列进行疏水性和跨膜区分析,构建了其分子进化树,在此基础上用同源建模方法构建了其天然态以及切除N端跨膜区后的三级结构,并对CYP725A4实现功能表达所必需的辅助还原酶也进行了天然态和切除N端跨膜区后的三级结构建模.所构建的结构模型经PROCHECK验证具有较好的可靠性.

英文摘要：

The difficulty in functional expression of CYP725A4 in heterogeneous prokaryotic hosts such as E.coli is a key bottleneck of the heterologous biosynthesis of taxol.In this paper,bioinformatic strategies were employed to analyze the hydrophobic profile and the transmembrane helices of CYP 725A4 sequence,and a molecular phylogenetic tree of CYP 725A4 was constructed.Then,based on the results,the tertiary structures of native and N-terminal truncated CYP 725A4 were reconstructed via the homology modeling,and similar operations were performed for native and truncated versions of cytochrome P450 reductase used for the functional expression of CYP 725A4.PROCHECK results show that the constructed structure models are all reliable.