Identifying protein targets of bioactive small molecules often requires complex, lengthy development of affinity probes. We present a method for stochastic modification of small molecules of interest with a photoactivatable phenyldiazirine linker. The resulting isomeric mixture is conjugated to a hydrophilic copolymer decorated with biotin and a fluorophore. We validated this approach using known inhibitors of several medicinally relevant enzymes. At least a portion of the stochastic derivatives retained their binding to the target, enabling target visualization, isolation, and identification. Moreover, the mix of stochastic probes could be separated into fractions and tested for binding affinity. The structure of the active probe could be determined and the probe resynthesized to improve binding efficiency. Our approach can thus enable rapid target isolation, identification, and visualization, while providing information required for subsequent synthesis of an optimized probe.

中文翻译：

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使用随机光修饰的探针鉴定生物活性小分子的蛋白质靶标

鉴定具有生物活性的小分子的蛋白质靶标通常需要复杂而漫长的亲和探针开发。我们提出了一种用光活化苯基二氮杂胺连接基随机修饰感兴趣的小分子的方法。将所得的异构体混合物缀合至装饰有生物素和荧光团的亲水性共聚物。我们使用几种医学上相关的酶的已知抑制剂验证了这种方法。至少一部分随机衍生物保留了它们与靶标的结合，从而使靶标可视化，分离和鉴定。此外，可以将随机探针的混合物分成多个部分并测试结合亲和力。可以确定活性探针的结构，并重新合成探针以提高结合效率。