We previously reported interaction determination using unpurified proteins (IDUP), a method to selectively amplify DNA sequences encoding ligand:target pairs from a mixture of DNA-linked small molecules and unpurified protein targets in cell lysates. In this study, we applied IDUP to libraries of DNA-encoded bioactive compounds and DNA-tagged human kinases to identify ligand:protein binding partners out of 32 096 possible combinations in a single solution-phase library × library experiment. The results recapitulated known small molecule:protein interactions and also revealed that ethacrynic acid is a novel ligand and inhibitor of MAP2K6 kinase. Ethacrynic acid inhibits MAP2K6 in part through alkylation of a nonconserved cysteine residue. This work validates the ability of IDUP to discover ligands for proteins of biomedical relevance.

中文翻译：

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从DNA编码的小分子文库×蛋白质文库选择中发现共价激酶抑制剂

我们先前报道了使用未纯化的蛋白质（IDUP）进行相互作用测定的方法，该方法可从细胞裂解液中DNA连接的小分子和未纯化的蛋白质靶标的混合物中选择性扩增编码配体：靶标对的DNA序列。在这项研究中，我们将IDUP应用于DNA编码的生物活性化合物和带有DNA标签的人类激酶的文库，以在单个溶液相文库×文库实验中鉴定出32 096种可能的组合中的配体：蛋白质结合伴侣。结果概括了已知的小分子：蛋白质相互作用，还揭示了乙炔酸是MAP2K6激酶的新型配体和抑制剂。乙二酸部分地通过非保守的半胱氨酸残基的烷基化抑制MAP2K6。这项工作验证了IDUP发现具有生物医学相关性蛋白质的配体的能力。