Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain.
Centre de Recherche en Biologie cellulaire de Montpellier, UMR 5237 CNRS, Université Montpellier, Montpellier 34090, France.
Biomacromolecules. 2020 Oct 12;21(10):4302-4312. doi: 10.1021/acs.biomac.0c01103. Epub 2020 Sep 21.
Natural selection has endorsed proteins with amazing structures and functionalities that cannot be matched by synthetic means, explaining the exponential interest in developing protein-based materials. Protein self-assembly allows fabricating complex supramolecular structures from relatively simple building blocks, a bottom-up strategy naturally employed by amyloid fibrils. However, the design of amyloid-inspired materials with biological activity is inherently difficult. Here, we exploit a modular procedure to generate functional amyloid nanostructures with tight control of their mesoscopic properties. The soft amyloid core of a yeast prion was fused to dihydrofolate reductase through flexible linkers of different sizes. This enabled us to produce, for the first time, biocompatible protein-only amyloid-like oligomeric nanoparticles with defined dimensions in which the embedded enzyme remained highly active, as assessed by biophysical and enzymatic assays. The modular design allowed one to obtain multifunctional nanoparticles by incorporating the antibody-binding Z-domain to the protein fusion. We show how these assemblies can be exploited for antibody-directed targeting of specific cell types and the localized delivery of methotrexate, resulting in the intracellular uptake of the drug by cancer cells and their death. Overall, the novel protein particles we describe in this work might find applications in areas as diverse as biocatalysis, bioimaging, or targeted therapies.
自然选择造就了具有惊人结构和功能的蛋白质，这些特性是合成手段无法比拟的，这也解释了人们对开发基于蛋白质的材料产生了巨大的兴趣。蛋白质自组装允许从相对简单的构建块构建复杂的超分子结构，这是淀粉样纤维自然采用的自下而上的策略。然而，设计具有生物活性的类淀粉样物质本质上具有挑战性。在这里，我们利用模块化程序来生成具有紧密介观特性控制的功能性淀粉样纳米结构。通过不同大小的柔性接头将酵母朊病毒的软淀粉样核心融合到二氢叶酸还原酶上。这使我们能够首次生产出具有确定尺寸的生物相容性的纯蛋白淀粉样低聚物纳米颗粒，其中嵌入的酶仍然保持高度活性，如通过生物物理和酶学测定评估的那样。模块化设计允许通过将抗体结合的 Z 结构域与蛋白质融合来获得多功能纳米颗粒。我们展示了这些组装体如何被用于针对特定细胞类型的抗体定向靶向和甲氨蝶呤的局部递送，从而导致癌细胞内药物摄取和死亡。总的来说，我们在这项工作中描述的新型蛋白质颗粒可能在生物催化、生物成像或靶向治疗等多个领域得到应用。
