THEORY OF AQUEOUS TWO-PHASE EXTRACTION

新的蛋白质分离技术的兴趣已经被激发， 近年来，由于基因工程的最新进展， 医疗行业对高纯度蛋白质的需求增加 和酶。 最需要的是恢复过程， 对重组蛋白和组成型蛋白足够温和 细胞内的蛋白质，但很容易适应大规模的 生产 满足这两个要求的技术是 用含水聚合物两相体系萃取，所述聚合物两相体系包含 聚乙二醇和葡聚糖，或聚乙二醇和 盐 拟议研究的目的是开发一种 一般的，全面的理论，基于统计力学， 蛋白质在两相聚合物水溶液中的溶解度， 没有盐。 这一理论有望提供对 负责蛋白质分配的分子机制。 的 目的是预测自由能，水相分离 和蛋白质分配系数作为蛋白质的函数 聚合物浓度，蛋白质和聚合物分子量， 蛋白质电荷、pH、蛋白质类型、聚合物类型、盐类型、离子 强度、温度和亲和配体的结合能。 该理论还应该允许预测盐的结合， 阳离子分配系数 单蛋白质分配 结果将根据分区的实验数据进行测试 溶菌酶、溶菌酶、苹果酸脱氢酶、人血清 白蛋白和过氧化氢酶。 多重蛋白质分配结果 将根据聚乙烯的实验数据进行测试 含有CO-血红蛋白的乙二醇/葡聚糖水溶液， 人血清白蛋白。 拟议的研究旨在 为现有数据的组织提供有用的框架 双水相萃取，并为新的优化设计 基于这种方法的生物回收工艺。

Interest in new protein isolation techniques has been stimulated in recent years by recent advances in genetic engineering and by increased demand from the medical sector for high purity proteins and enzymes. Most needed are recovery processes which are gentle enough for recombinant proteins and constitutive intracellular proteins, and yet are easily adapted to large-scale production. A technique which fulfills both requirements is extraction with aqueous polymer two-phase systems containing either polyethylene glycol and dextran, or polyethylene glycol and salt. The aim of the proposed research is the development of a general, comprehensive theory, based in statistical mechanics of protein solubility in two-phase aqueous polymer solutions with or without salt. The theory is expected to provide insight into the molecular mechanisms responsible for protein partitioning. The objective is to predict free energies, aqueous phase separations and protein partition coefficients as a function of protein and polymer concentrations, protein and polymer molecular weights, protein charge, pH, protein type, polymer type, salt type, ionic strength, temperature, and the binding energy of affinity ligands. The theory should also allow the prediction of salt union and cation partition coefficients. The single protein partitioning results will be test against experimental data on the partitioning of lysozyme, fumarase, malate-dehydrogenase, human serum albumin, and catalase. The multiple protein partitioning results will be tested against experimental data on polyethylene glycol/dextran aqueous solutions containing CO-hemoglobin and human serum albumin. The proposed research is intended to provide a useful framework for the organization of existing data aqueous two-phase extraction and for the optimal design of new biorecovery processes based on this method.