DNA aptamers are attractive capture probes for affinity chromatography since, in contrast to antibodies, they can be chemically synthesized and, in contrast to tag-specific capture probes (such as Nickel-NTA or Glutathione), they can be used for purification of proteins free of genetic modifications (such as His or GST tags). Despite these attractive features of aptamers as capture probes, there are only a few reports on aptamer-based protein purification and none of them includes a test of the purified protein's activity, thus, leaving discouraging doubts about method’s ability to purify proteins in their active state. The goal of this work was to prove that aptamers could facilitate isolation of active proteins. We refined a complete aptamer-based affinity purification procedure, which takes 4 h to complete. We further applied this procedure to purify two recombinant proteins, MutS and AlkB, from bacterial cell culture: 0.21 mg of 85%-pure AlkB from 4 mL of culture and 0.24 mg of 82%-pure MutS from 0.5 mL of culture. Finally, we proved protein activity by two capillary electrophoresis based assays: an enzymatic assay for AlkB and a DNA-binding assay for MutS. We suggest that in combination with aptamer selection for non-purified protein targets in crude cell lysate, aptamer-based purification provides a means of fast isolation of tag-free recombinant proteins in their native state without the use of antibodies.

DNA适体是亲和色谱的诱人捕获探针，因为与抗体相反，它们可以化学合成，并且与标签特异性捕获探针（例如Nickel-NTA或Glutathione）相比，它们可以用于纯化不含蛋白质的蛋白基因修饰（例如His或GST标签）。尽管适体具有捕获探针的这些吸引人的功能，但仅有少数关于基于适体的蛋白质纯化的报道，而且都没有对纯化的蛋白质的活性进行测试，因此，对方法纯化处于活性状态的蛋白质的能力的疑虑不容置疑。 。这项工作的目的是证明适体可以促进活性蛋白的分离。我们完善了一个完整的基于适体的亲和纯化程序，该过程需要4小时才能完成。我们进一步应用了该程序，从细菌细胞培养物中纯化了两种重组蛋白MutS和AlkB：0.21 mg的85％纯AlkB（来自4 mL培养物）和0.24 mg的82％纯度MutS（来自0.5 mL培养物）。最后，我们通过两种基于毛细管电泳的测定法证明了蛋白质的活性：AlkB的酶法测定法和MutS的DNA结合测定法。我们建议与针对粗细胞裂解物中非纯化蛋白靶标的适体选择相结合，基于适体的纯化提供了一种快速分离天然状态下无标签重组蛋白而无需使用抗体的方法。我们通过两种基于毛细管电泳的测定法证明了蛋白质的活性：AlkB的酶法测定法和MutS的DNA结合测定法。我们建议与针对粗细胞裂解物中非纯化蛋白靶标的适体选择相结合，基于适体的纯化提供了一种快速分离天然状态下无标签重组蛋白而无需使用抗体的方法。我们通过两种基于毛细管电泳的测定法证明了蛋白质的活性：AlkB的酶法测定法和MutS的DNA结合测定法。我们建议与针对粗细胞裂解物中非纯化蛋白靶标的适体选择相结合，基于适体的纯化提供了一种快速分离天然状态下无标签重组蛋白而无需使用抗体的方法。