Investigation of Interaction Between Lactoferrin and Bio-Molecules

乳铁蛋白的生物学功能已被明确，如抑菌作用、骨髓生成、铁结合等。因此，乳铁蛋白在食品、医药和饲料中的应用潜力一直是人们研究的热点。人们认为乳铁蛋白最基本的功能之一是作为各种配体的载体，如金属、药物等低分子量和高分子量物质。因此，本课题采用分光光度法研究了乳铁蛋白与NAD或NADP类似物质Cibacron蓝F3GA染料的相互作用性质。用圆二色光谱在250 ~ 400 nm波长范围内观察了染料与乳铁蛋白结合诱导的棉花效应。从这个现象。与乳铁蛋白结合的染料数量估计为6摩尔/摩尔。而这一数值在过乳铁蛋白和饱和铁乳铁蛋白中是相同的。另一方面，人乳铁蛋白对固定化Cibacron蓝的结合能力弱于牛乳铁蛋白。这种差异可能是由于牛和人乳铁蛋白的pI值不同。因此，实验测定了人和牛乳铁蛋白的pI值。

The biological functions of lactoferrin have been characterized, such as its bacteriostatic effects, myelopoiesis, iron binding, and others. Therefore, The potential of utilization of lactoferrin in food, medicine and feed has remained the subject of intense investigation. It is supposed that one of the most fundamental functions of lactoferrin is the carrier of various ligands such as metals, drugs and other low molecular weight and high molecular weight substances. Thus, in this research project, the interacting properties of lactoferrin with dye, Cibacron blue F3GA, which is an analogous material of NAD or NADP, has been investigated by the spectrophotometric method. Cotton effect induced by the dye binding to lactoferrin was observed by circular dichroism spectra in the wavelength range between 250 and 400 nm. From this phenomenon. The number of dye bound to lactoferrin was estimatedto be 6 moles/mole. And this number was the same with both of apolactoferrin and iron-saturated lactoferrcn.On the other hand, the binding property of human lactoferrin against immobilized Cibacron blue was weaker than that of bovine lactoferrin. This difference may be due to the difference of pI values of bovine and human lactoferrins. Thus, both pI values of human and bovine lactoferrins were experimentally determined.