摘要
目的 :研究富硒培养的钝顶螺旋藻干藻 (含硒 :4 62 .6μg·g- 1)中蛋白质含硒量及差异 .方法 :采用硫酸铵分级、DEAE - 52纤维素及SephadexG - 10 0柱层析分离纯化蛋白质 ;经紫外吸收光谱和SDS梯度凝胶电泳检测蛋白质纯度及亚基组成 ;以 2 ,3-二氨基萘 (DAN)荧光分光光度法测定含硒量 .结果 :蛋白质结合的硒占藻体总硒的 58.7% ;不同饱和度 ( 2 5%、50 %、10 0 % )硫酸铵分级沉淀蛋白质中的硒占总硒的情况分别为 4 .6%、18.7%、6.5% ;DEAE - 52柱层析蛋白洗脱峰蛋白含硒量依次为 2 58、4 31、2 0 4、4 84 μg·g- 1;分离纯化的含硒藻蓝蛋白有较高的含硒量 ( 2 67μg·g- 1) ,两个亚基相对分子质量为α =1950 0 ,β =2 150 0 ,两亚基含硒量相对之比为 1.65.结论
Aim:Various Se contents in different proteins of Se-enriched Spirulina platensis ( Dry powder of S .P., Se content was 462.6 μg·g -1 ) were investigated. Methods:Proteins were isolated with different concentrations of ammonium sulfate and purified with anion exchange (DEAE-52) and Sephedax G-100 column chromatography. Ultraviolet visible spectra and gradient SDS-PAGE were conducted to identify the purity and subunits of the Se-containing phycocyanin (Se-PC). Se content was determined by 2,3-DAN fluorimetry. Results: 1) 58.7% of total Se was bound to proteins in Se-enriched S.P .; 2) Relative contents of Se in various precipitates isolated with different concentrations of ammonium sulfate (25%, 50%, 100%) were 4.6%, 18.7% and 6.5%; 3) Se contents in protein of four peaks on DEAE-52 column chromatography were 258, 431, 204, 484 μg·g -1 ; 4) Se content of Se-PC was 267 μg·g -1 and results of gradient SDS-PAGE indicated that relative molecular weights of α and β subunits of Se-PC were 19 500 and 21 500 . The ratio of Se in α and β subunits of Se-PC was 1.65. Conclusion: These results showed that Se was bound to proteins of Se-enriched S.P., and suggested that various proteins, including subunits of phycocyanin, bound Se to different extents . [
出处
《暨南大学学报（自然科学与医学版）》
CAS
CSCD
2001年第3期86-90,共5页
Journal of Jinan University(Natural Science & Medicine Edition)
基金
广东省科委基金资助项目!(970 6 30 )
