摘要
通过凝胶层析方法 ,对水稻籽实中的蛋白质 Cd、Pb结合形态特征及其稳定性进行了研究 .结果表明 :水稻籽实Tris HCl提取液经SephadexG 75分离 ,洗脱液得到 3个紫外吸收峰 ,在第 1、3峰处出现了Cd、Pb浓度峰 ,其蛋白质 Cd、Pb结合体的表观分子量为 5 4.5KD和 5 .5KD .在蒸煮加热处理后 ,水稻籽实中蛋白质 Cd、Pb结合体发生变性 ,使分子量为 5 4.5KD的蛋白质 Cd、Pb结合体完全破坏 ,分子量为 5 .5KD的结合体也部分地被破坏 ,与蛋白质结合的Cd、Pb被释放出来 .胃蛋白酶和胰蛋白酶消化处理后 ,也能够破坏蛋白质 Cd、Pb结合体的形态 ,洗脱液中Cd、Pb的浓度分布也发生了变化 ,在第 1、3紫外吸收峰处的Cd、Pb浓度也明显降低 .另外 ,在第 3峰以后的洗脱液中也检测到Cd。
The protein binding forms of Cd and Pb in polluted rice seed and their tability were studied using Sephadex chromatography. Three peaks of absorption for Tris HCl extraction from rice on Sephadex G 75 were detected. The Cd and Pb distributed mainly in the fractions of F ⒈ and F Ⅲ. The apparent molecular weights of proteins Cd and Pb for F Ⅰ and F Ⅲ were 54.5 and 5.5KD, respectively. After the treatment of cooking, the protein binding forms of Cd and Pb were destroyed, high molecular weight protein binding form (54.5KD) was decomposed into low molecular weight complex (5.5KD) or tiny peptide chain. Simultaneously, bound Cd and Pb were released or from protein changed into small protein binding forms. After the treatment of enzyme digestion, the high molecular weight protein binding forms of Cd and Pb were decomposed the concentrations of Cd amd Pb in the elutions of first and third peak decreased markedly, and the Cd and Pb appeared in the elution of third peak later.
出处
《环境科学学报》
CAS
CSCD
北大核心
2001年第2期213-217,共5页
Acta Scientiae Circumstantiae
基金
国家自然科学基金! (4 97710 6 9)资助
