The caged bird sings: The natural ferritin nanocage from Archaeoglobus fulgidus can encapsulate positively charged proteins (green) within its lumenal cavity through electrostatic interactions. Enzymes (gray) attached to such charged guests retain their activity [substrate (S)product (P)], thus equipping the ferritin cages with new catalytic functions and opening new avenues for their use in nanotechnology and pharmacology.

中文翻译：

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铁蛋白笼的酶包封

笼中的鸟会唱歌：来自古细菌的天然铁蛋白纳米笼可以通过静电相互作用将带正电荷的蛋白质（绿色）包裹在其腔内。附着在此类带电客人身上的酶（灰色）保持其活性[底物（S）产品（P）]，从而为铁蛋白笼子配备了新的催化功能，并为它们在纳米技术和药理学中的使用开辟了新途径。