[Objective] The paper was to study the changes of protein content and component in leaves of Toona Sinensis under low-temperature stress.[Method] Potted experiment was adopted,and SDS-PAGE electrophoresis was also used to analyze the dynamic changes of protein in T.Sinensis leaves.[Result] Low temperature stress could change the content and component in leaves of T.Sinensis,but different provenances had different performance under different temperatures,so did the same provenance under different stress periods.SDS-PAGE electrophoresis results indicated that the change law of provenances of Xixia of Henan and Nanjing of Jiangsu with stronger cold resistance was similar,showing the change trend of "increase-decrease-increase".Protein was greatly expressed after stress for 1 d,the color of band became darker;the content gradually decreased in the following second and third day,and the color of bands was lighter;the content began to increase at the forth day.Two provenances induced the specific proteins with molecular weights of 27.6 and 22.5 kD,respectively.The soluble protein content of provenance of Xiapu of Fujian with relatively weak cold resistance was gradually increased,but no new protein bands were induced.The changes of protein band color of various provenances in SDS-PAGE electrophoresis was basically consistent with the changes of protein content,the provenance with stronger cold resistance could induce the production of specific proteins.[Conclusion] The study provided theoretical basis for under the molecular mechanism of plant cold resistance,which had great significance in theory and practice.
以蛋白质提取率为考察指标,选取不同溶液提取银杏营养贮藏蛋白质;运用均匀设计法考察提取时间,提取液pH值、浓度和液料比等对银杏营养贮藏蛋白质提取率的影响,得到了蛋白质提取率的回归模型.经优化筛选后得到如下工艺参数:提取时间为10 h,提取pH为9.0,提取液Tris-HCl浓度为0.25 mol.L-1,提取液液料比为10∶1.在此条件下蛋白质提取率为70.22%.SDS-PAGE电泳分析结果表明,该蛋白质提取液主要含有15、18、23、32、36和44 ku 6种蛋白质.
Glycoprotein from Ginkgo biloba kernel may be allergic. In this paper, the allergic proteins were identified with Western blotting, and the 32 kDa glycoprotein was purified with ion exchange chromatography and gel chromatography. With Western blotting, there were 3 allergic proteins with molecular weight 21, 32, and 36 kDa. With SDS-PAGE analysis and measurements of the protein and sugar contents, the isolation and purification technology of 32 kDa was confirmed. Ginkgo crude protein extract was precipitated with ammonium sulphate （saturation gradient： 40-80%）. The precipitate was purified by chromatography with DEAE-cellulose 52, then chromatography with Sephadex G-200 and the target glycoprotein was finally obtained. The analysis results showed the molecule of the glycoprotein was 32.12 kDa and the ratio of protein to sugar was 20.56：1. In conclusion, the purification method could be used in preparation of the glycoprotein, and the study could provide a basis for the further research of the glycoprotein.
YANG Jian-tingWU Cai-eLI Ying-yingJIA Shao-qianFAN Gong-jianPENG Fang-ren
