In the past two decades, amyloids, typically associated with human diseases, have been described to play various functional roles in nearly all life forms. The structural and functional diversity of microbial 'functional amyloids' has dramatically increased in recent years, expanding the canonical definition of these assembled molecules. Here, we provide a broad review of the current understanding of microbial functional amyloids and their diverse roles, putting the spotlight on recent discoveries in the field. We discuss their functions as structural scaffolds, surface-tension modulators, adhesion molecules, cell-cycle and gametogenesis regulators, toxins, and mediators of host–pathogen interactions. We outline how noncanonical amyloid morphologies and sophisticated regulatory mechanisms underlie their functional diversity and emphasize their therapeutic and biotechnological implications and applications.

在过去的二十年中，通常与人类疾病相关的淀粉样蛋白被描述为在几乎所有生命形式中发挥各种功能作用。近年来，微生物“功能性淀粉样蛋白”的结构和功能多样性急剧增加，扩大了这些组装分子的规范定义。在这里，我们广泛回顾了目前对微生物功能性淀粉样蛋白及其不同作用的理解，重点关注该领域的最新发现。我们讨论了它们作为结构支架、表面张力调节剂、粘附分子、细胞周期和配子发生调节剂、毒素和宿主-病原体相互作用的介质的功能。