摘要
为了进一步研究杨树4CL基因,以毛白杨为材料克隆到一个新的毛白杨4CL3基因。生物信息学分析结果显示:该基因和其他4CL基因一样含有4CL基因家族2个保守框Box I和Box II。将4CL3基因连接至原核表达载体pQE30,表达纯化后测定其蛋白的比活力,结果显示:4CL3基因对不同底物表现出了不同的催化效率。对该基因的最适温度和最适pH值测定后发现:4CL蛋白的最适温度为40℃,最适pH值为8.5,且在pH=9.0时有60%的活力。采用HPLC-MS的方法,分析了4CL3蛋白对混合底物的催化情况,结果显示:在混合底物下,4CL3蛋白对4-香豆酸、阿魏酸和肉桂酸都表现较高的活力,而对芥子酸和咖啡酸没有活力。
A new 4CL gene from Populus tomentosa Can. was cloned and named as 4CL3. Bioinformatics method was used to analysis the protein sequence of this 4CL3 gene aligning with two other 4CL proteins. The authors found the conserved sequence Box I and Box II exist in the 4CL gene family. Prokaryotic expression way was used to re- search the enzyme function of this 4CL3 protein, the result showed that the 4CL protein had different enzymatic ac- tivity towards the different substrate. The 4CL3 protein had the biggest enzymatic activity at the temperature of 40 ~C, and it had the biggest enzymatic activity at pH 8.5, this enzyme has the ability of resisting alkaline environ- ment. The 5 substrates of 4CL were mixed and the method of HPLC-MS was used to survey the consumption of the substrate after putting 4CL enzyme to start the reaction. It was found that besides sinapic there was no consumption of caffeic either.
出处
《林业科学研究》
CSCD
北大核心
2013年第5期542-547,共6页
Forest Research
基金
北京市教育委员会科学研究与研究生培养共建项目-学科建设-森林培育(20120618)
