State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People's Republic of China.
Biomacromolecules. 2024 Nov 11;25(11):7191-7201. doi: 10.1021/acs.biomac.4c00864. Epub 2024 Oct 11.
Biomolecular condensates are distinct subcellular structures with on-demand material states and dynamics in living cells. However, strategies for modulating their material states and physicochemical properties are lacking. Here, we report a chemical strategy for modulating the condensate states of intrinsically disordered proteins in bacterial cells. This is achieved by noncanonical amino acid (DOPA) incorporation into model resilin-like proteins (RLPs) to endow autonomous oxidative and coordinative cross-linking mechanisms. Biogenesis of spherical gel-like condensates is achieved upon heterologous expression of the DOPA-incorporated RLP in the cells at 30 °C. We reveal that liquid-liquid phase separation underlies the formation of liquid condensates, and this liquid-like state is metastable and its dynamics is compromised by the oxidative and coordinative cross-linkings that ultimately drive the liquid-to-gel transition. Therefore, this study has deepened our understanding of biomolecular condensation and offers a new chemical strategy to expand the landscape of condensation phenotypes of living cells.
生物分子凝聚物是具有按需物质状态和动态的独特亚细胞结构。然而，调节其物质状态和物理化学性质的策略却很缺乏。在这里，我们报告了一种在细菌细胞中调节无规卷曲蛋白质凝聚物状态的化学策略。这是通过将非典型氨基酸（DOPA）掺入到模型弹性蛋白样蛋白（RLP）中来实现的，从而赋予其自主氧化和协调交联机制。在 30°C 下，将 DOPA 掺入的 RLP 异源表达于细胞中，可形成球形凝胶状凝聚物。我们揭示了液-液相分离是液体凝聚物形成的基础，这种液态是亚稳态的，其动力学受到氧化和协调交联的影响，最终导致液体到凝胶的转变。因此，这项研究加深了我们对生物分子凝聚的理解，并提供了一种新的化学策略来扩展活细胞凝聚表型的范围。
