乳腺生物反应器表达的重组人乳铁蛋白的分离纯化及生物活性鉴定  

Purification and characterization of recombinant human lactoferrin expressed in a cattle mammary bioreactor

作　　者：白倩[1,2] 张焱[2] 汪音爵[2] 罗坚[2] 李岩[2] 黄永东[2] 马润宇[1] 苏志国[2] 

机构地区：[1]北京化工大学生命科学与技术学院,北京100029 [2]中国科学院过程工程研究所生化工程国家重点实验室,北京100190

出　　处：《生物工程学报》2010年第11期1576-1583,共8页Chinese Journal of Biotechnology

基　　金：国家高技术研究发展计划(863计划)(Nos.2007AA100506;2010AA100501);国家自然科学基金(No.20706052)资助~~

摘　　要：以国产高交联度的快流速琼脂糖为基质,合成了不同配基密度的SP(Sulfopropyl,磺酸基)离子交换介质,建立了乳腺生物反应器表达重组人乳铁蛋白(Recombinant Human Lactoferrin,rHLF)的纯化方法。以溶菌酶为模型蛋白考察了不同配基密度离子交换介质的静态和动态吸附行为,结果表明介质具有良好的吸附性能。不同配基密度离子交换介质均可纯化得到rHLF,其中,高配基密度(0.24mol/L)的离子交换介质每毫升可以处理50mL rHLF牛乳,rHLF收率为86.5%,纯度为98.5%。圆二色谱的测定结果表明纯化的rHLF二级结构与天然人乳铁蛋白一致。生物学功能实验结果表明,rHLF的铁结合与释放活性与天然人乳铁蛋白相似,浓度为5g/L的rHLF对大肠杆菌的生长具有明显的抑制作用。Novel ion exchange adsorbents were synthesized by immobilizing sulfopropyl derivative onto homemade highly cross-linked agarose beads.The effects of different ligand densities（from 0.05 to 0.24 mol/L）on static and dynamic adsorption of the adsorbents were investigated using lysozyme as a model protein.Based on these results,rHLF was purified from the transgenic milk by our SP media.1 mL high density（0.24 mol/L）adsorbent could handle 50 mL rHLF-containing milk.The mass recovery of rHLF was 86.5%and the purity was 98.5%.CD spectra demonstrated that the native structure of rHLF was not affected in the purification process.The biological functions of the purified rHLF,including iron binding,releasing and antimicrobial activities were then investigated.The results showed that rHLF had comparable iron binding and releasing activity to that of native HLF.5 g/L concentration of rHLF significantly inhibited the growth of Escherichia coli.These studies lay a solid foundation for the wide application of our self-prepared ion exchange adsorbents in protein purification.

关 键 词：离子交换介质 配基密度 重组人乳铁蛋白 纯化 抑菌活性 

分 类 号：Q814[生物学—生物工程]