Practice question

Inclusion bodies represent dense, insoluble cytoplasmic aggregates of misfolded recombinant protein accumulating in Escherichia coli during overexpression. High synthesis rates under strong promoters saturate GroEL, DnaK chaperone pathways, exposing hydrophobic patches that promote intermolecular association. Insufficient time for proper folding, absence of eukaryotic folding catalysts, and reducing environment preventing disulfide formation further exacerbate aggregation. Aggregates are refractile, biologically inactive, and require chaotropic agents for solubilization. Their formation reflects protein quality control failure rather than growth rate, protease action, or DNA recombination deficiency alone.