Natural products perennially serve as prolific sources of drug leads and chemical probes, fueling the development of numerous therapeutics. Despite their scarcity, natural products that modulate protein function through covalent interactions with lysine residues hold immense potential to unlock new therapeutic interventions and advance our understanding of the biological processes governed by these modifications. Phloroglucinol meroterpenoids constitute one of the most expansive classes of natural products, displaying a plethora of biological activities. However, their mechanism of action and cellular targets have, until now, remained elusive. In this study, we detail the concise biomimetic synthesis, computational mechanistic insights, physicochemical attributes, kinetic parameters, molecular mechanism of action, and functional cellular targets of several phloroglucinol meroterpenoids. We harness synthetic clickable analogues of natural products to probe their disparate proteome-wide reactivity and subcellular localization through in-gel fluorescence scanning and cell imaging. By implementing sample multiplexing and a redesigned lysine-targeting probe, we streamline a quantitative activity-based protein profiling, enabling the direct mapping of global reactivity and ligandability of proteinaceous lysines in human cells. Leveraging this framework, we identify numerous lysine–meroterpenoid interactions in breast cancer cells at tractable protein sites across diverse structural and functional classes, including those historically deemed undruggable. We validate that phloroglucinol meroterpenoids perturb biochemical functions through stereoselective and site-specific modification of lysines in proteins vital for breast cancer metabolism, including lipid signaling, mitochondrial respiration, and glycolysis. These findings underscore the broad potential of phloroglucinol meroterpenoids for targeting functional lysines in the human proteome.

中文翻译：

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仿生合成和化学蛋白质组学揭示间苯三酚小萜类化合物的作用机制和功能靶点

天然产物一直是药物先导物和化学探针的丰富来源，推动了众多治疗方法的发展。尽管它们很稀缺，但通过与赖氨酸残基的共价相互作用调节蛋白质功能的天然产物具有巨大的潜力，可以解锁新的治疗干预措施，并增进我们对这些修饰控制的生物过程的理解。间苯三酚类萜是最广泛的天然产物类别之一，具有多种生物活性。然而，迄今为止，它们的作用机制和细胞靶点仍然难以捉摸。在这项研究中，我们详细介绍了几种间苯三酚类萜的简明仿生合成、计算机制见解、理化属性、动力学参数、分子作用机制和功能性细胞靶标。我们利用天然产物的合成可点击类似物，通过凝胶内荧光扫描和细胞成像来探测其不同的蛋白质组反应性和亚细胞定位。通过实施样品多重分析和重新设计的赖氨酸靶向探针，我们简化了基于活性的定量蛋白质分析，从而能够直接绘制人类细胞中蛋白质赖氨酸的整体反应性和配体性。利用这个框架，我们在乳腺癌细胞中跨不同结构和功能类别的易处理蛋白质位点上发现了许多赖氨酸-类萜相互作用，包括那些历史上被认为不可成药的蛋白质位点。我们验证了间苯三酚美萜类化合物通过对乳腺癌代谢至关重要的蛋白质中的赖氨酸进行立体选择性和位点特异性修饰来扰乱生化功能，包括脂质信号传导、线粒体呼吸和糖酵解。这些发现强调了间苯三酚类萜类化合物在靶向人类蛋白质组中的功能性赖氨酸方面的广泛潜力。