“…Common examples are the following: (1) formation of inclusion bodies in E. coli that have been engineered by recombinant DNA technology to overexpress heterologous proteins (Uren, 1984); (2) precipitation of heat-treated globular proteins (Privalov, 1979); and (3) irreversibility of protein renaturation due to aggregation (Light, 1985). Apparent irreversibility of in vitro refolding was reported for tryptophanase (London et al, 1974), 0-galactosidase (Goldberg, 1972, catalytic subunit of aspartate transcarbamylase (Ghelis & Hervé, 1978), elastase (Zilber, 1979), the dehydrogenases (Jaenicke & Rudolph, 1983), rhodanese (Horowitz & Criscimagna, 1986), phosphorylase b (Price & Stevens, 1983), and antithrombin (Fish et al, 1985). For these proteins, the irreversibility of refolding was shown to occur only at critical concentrations of denaturant.…”