Protein aggregation as bacterial inclusion bodies is reversible

FEBS Letters

Villaverde, Antonio¹  Carrió, M.Mar¹ 

[1] Institut de Biologia Fonamental and Departament de Genètica and Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain

关键词: Inclusion body;    Protein aggregation;    Refolding;    Recombinant protein;    β-Galactosidase;    TSP;   

DOI  :  10.1016/S0014-5793(01)02073-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Inclusion bodies are refractile, intracellular protein aggregates usually observed in bacteria upon targeted gene overexpression. Since their occurrence has a major economical impact in protein production bio-processes, in vitro refolding strategies are under continuous exploration. In this work, we prove spontaneous in vivo release of both β-galactosidase and P22 tailspike polypeptides from inclusion bodies resulting in their almost complete disintegration and in the concomitant appearance of soluble, properly folded native proteins with full biological activity. Since, in particular, the tailspike protein exhibits an unusually slow and complex folding pathway involving deep interdigitation of β-sheet structures, its in vivo refolding indicates that bacterial inclusion body proteins are not collapsed into an irreversible unfolded state. Then, inclusion bodies can be observed as transient deposits of folding-prone polypeptides, resulting from an unbalanced equilibrium between in vivo protein precipitation and refolding that can be actively displaced by arresting protein synthesis. The observation that the formation of big inclusion bodies is reversible in vivo can be also relevant in the context of amyloid diseases, in which deposition of important amounts of aggregated protein initiates the pathogenic process.

【 授权许可】

Unknown