Practice question

Expression of eukaryotic proteins in prokaryotic host Escherichia coli often yields inactive product due to multiple physiological mismatches. Codon bias differs; rare eukaryotic codons cause ribosome stalling, premature termination, and truncation. Prokaryotes lack endoplasmic reticulum machinery for N-glycosylation, disulfide isomerization, and other post-translational modifications essential for stability and activity. Molecular chaperone systems and folding environments also differ, leading to misfolding, aggregation into inclusion bodies, and proteolytic degradation. Combined effects explain multifactorial loss of function requiring eukaryotic hosts or engineered bacterial strains for rescue.