Institute for Biotechnology and Biomedicine, Autonomous University of Barcelona, 08193, Bellaterra, Barcelona, Spain.
Department of Genetics and Microbiology, Autonomous University of Barcelona, 08193, Bellaterra, Barcelona, Spain.
Microb Cell Fact. 2021 Feb 2;20(1):30. doi: 10.1186/s12934-021-01524-3.
Protein aggregation is a biological event observed in expression systems in which the recombinant protein is produced under stressful conditions surpassing the homeostasis of the protein quality control system. In addition, protein aggregation is also related to conformational diseases in animals as transmissible prion diseases or non-transmissible neurodegenerative diseases including Alzheimer, Parkinson's disease, amyloidosis and multiple system atrophy among others. At the molecular level, the presence of aggregation-prone domains in protein molecules act as seeding igniters to induce the accumulation of protein molecules in protease-resistant clusters by intermolecular interactions.
In this work we have studied the aggregating-prone performance of a small peptide (L6K2) with additional antimicrobial activity and we have elucidated the relevance of the accompanying scaffold protein to enhance the aggregating profile of the fusion protein. Furthermore, we demonstrated that the fusion of L6K2 to highly soluble recombinant proteins directs the protein to inclusion bodies (IBs) in E. coli through stereospecific interactions in the presence of an insoluble protein displaying the same aggregating-prone peptide (APP).
These data suggest that the molecular bases of protein aggregation are related to the net balance of protein aggregation potential and not only to the presence of APPs. This is then presented as a generic platform to generate hybrid protein aggregates in microbial cell factories for biopharmaceutical and biotechnological applications.
蛋白质聚集是一种在表达系统中观察到的生物学事件，其中重组蛋白在超过蛋白质质量控制系统的内稳态的应激条件下产生。此外，蛋白质聚集还与动物中的构象疾病有关，包括传染性朊病毒病或非传染性神经退行性疾病，如阿尔茨海默病、帕金森病、淀粉样变性和多系统萎缩等。在分子水平上，蛋白质分子中存在易于聚集的结构域，作为引发聚集的点火器，通过分子间相互作用诱导蛋白酶抗性聚集体中蛋白质分子的积累。
在这项工作中，我们研究了具有额外抗菌活性的小肽（L6K2）的聚集倾向性能，并阐明了伴随的支架蛋白的相关性，以增强融合蛋白的聚集特性。此外，我们证明了 L6K2 与高度可溶性重组蛋白的融合通过在存在显示相同易于聚集肽（APP）的不溶性蛋白的情况下的立体特异性相互作用，将蛋白引导到大肠杆菌中的包涵体（IBs）中。
这些数据表明，蛋白质聚集的分子基础与蛋白质聚集潜力的净平衡有关，而不仅仅与 APP 的存在有关。这随后被提出作为在微生物细胞工厂中生成混合蛋白聚集体的通用平台，用于生物制药和生物技术应用。
