Department of General and Medical Biochemistry, Faculty of Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland.
Molecules. 2023 Sep 12;28(18):6582. doi: 10.3390/molecules28186582.
Liquid-liquid phase separation (LLPS) and the formation of membraneless organelles (MLOs) contribute to the spatiotemporal organization of various physiological processes in the cell. These phenomena have been studied and characterized mainly in eukaryotic cells. However, increasing evidence indicates that LLPS-driven protein condensation may also occur in prokaryotes. Recent studies indicate that aggregates formed during proteotoxic stresses may also play the role of MLOs and increase the fitness of bacteria under stress. The beneficial effect of aggregates may result from the sequestration and protection of proteins against irreversible inactivation or degradation, activation of the protein quality control system and induction of dormancy. The most common stress that bacteria encounter in the natural environment is water loss. Therefore, in this review, we focus on protein aggregates formed in upon desiccation-rehydration stress. In silico analyses suggest that various mechanisms and interactions are responsible for their formation, including LLPS, disordered sequences and aggregation-prone regions. These data support findings that intrinsically disordered proteins and LLPS may contribute to desiccation tolerance not only in eukaryotic cells but also in bacteria. LLPS-driven aggregation may be a strategy used by pathogens to survive antibiotic treatment and desiccation stress in the hospital environment.
液-液相分离 (LLPS) 和无膜细胞器 (MLO) 的形成有助于细胞内各种生理过程的时空组织。这些现象主要在真核细胞中进行了研究和表征。然而，越来越多的证据表明，LLPS 驱动的蛋白质凝聚也可能发生在原核生物中。最近的研究表明，在蛋白毒性应激下形成的聚集体也可能发挥 MLO 的作用，并提高细菌在应激下的适应性。聚集体的有益效应可能源于对蛋白质的隔离和保护，防止其不可逆失活或降解、激活蛋白质质量控制系统和诱导休眠。细菌在自然环境中最常遇到的应激是失水。因此，在这篇综述中，我们重点讨论了在干燥-复水应激下形成的蛋白质聚集体。计算机分析表明，各种机制和相互作用负责其形成，包括 LLPS、无序序列和易于聚集的区域。这些数据支持了这样的发现，即无序蛋白质和 LLPS 不仅可能有助于真核细胞的干燥耐受性，也可能有助于细菌的干燥耐受性。LLPS 驱动的聚集可能是病原体在医院环境中对抗生素治疗和干燥应激生存的一种策略。
