Chiral copper-chelate complexes alter selectivities in metal affinity protein partitioning.
Chiral copper-chelate complexes alter selectivities in metal affinity protein partitioning.
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DOI：
10.1016/s0021-9673(01)95786-3
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发表时间：
1991
期刊：
影响因子：
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通讯作者：
G. Wuenschell;E. Wen;R. Todd;D. Shnek;F. Arnold
中科院分区：
文献类型：
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作者：
G. Wuenschell;E. Wen;R. Todd;D. Shnek;F. Arnold
在金属亲和分离中，利用组氨酸微环境和金属螯合配体之间的互补性可以区分蛋白质。本文研究了三种肌红蛋白在聚乙二醇-葡聚糖双水相体系中的分配行为。用甲硫氨酸络合物衍生化的TSK色谱支持物用于研究这些蛋白质在金属亲和色谱中的保留。在分区研究中，氨基酸金属螯合物表现出不同的Cu（II）-亚氨基二乙酸的肌红蛋白的选择性。基于氨基酸复合物的手性性质的选择性的显着差异也obsrved。的螯合配体的色谱选择性表现出很小的变化，但是，这表明在溶液中发生的相互作用，但不是在表面上发挥重要作用，在蛋白质结合的Cu（II）-氨基酸-PEG复合物。在溶液中，Cu（II）-氨基酸配合物是表面组氨酸微环境的敏感探针。金属螯合亲和配体的选择提供了一种强有力的手段，通过这种手段可以改变金属亲和分离的选择性。
Proteins can be distinguished by exploiting complementarity between a histidine's microenvironment and a metal—chelate ligand in metal-affinity separations. The partitioning behavior of three myoglobins was investigated in aqueous two-phase polyethylene glycol—dextran systems containing polyethylene glycol derivatized with Cu(II) complexes of thel- andd-isomers of methionine and aspartate. TSK chromatographic supports derivatized with the methionine complexes were used to study retention of these proteins in metal-affinity chromatography. In partitioning studies, the amino acid metal chelates exhibit selectivities for the myoglobins that are different from that of Cu(II)-iminodiacetate. Significant differences in selectivity based on the chiral nature of the amino acid complexes were also obsrved. The chromatographic selectivities of the chelating ligands exhibit little variation, however, suggesting that interactions occuring in solution but not on a surface play an important role in protein binding to the Cu(II)-aminoa acid-PEG complexes. In solution, the Cu(II)-amino acid complexes are sensitive probes of the microenvironments of surface histidines. The choice of the metal chelate affinity ligand offers a powerful means by which the selecitivity of metal-affinity separations can be altered.