Paradigm Shifts in our Views on Inclusion Bodies

Inclusion bodies (IBs) are often produced during overexpression of recombinant proteins in E.coli. These were initially perceived as amorphous aggregates of misfolded (and hence inactive) protein molecules. It turns out that in many cases, IBs contain varying amount of native like structures and show different extent of biological activity. At the same time, IBs perhaps differ only qualitatively from amyloids in having β-sheet structures. It seems likely that precipitates, IBs and amyloids represent different trade off points to achieve thermodynamic stability at the cost of biological activity.