ABSTRACT
Speed, M., King, J. and Wang, D.I.C. (1997) Biotechnology and Bioengineering, 54, 333-343
Polymerization Mechanism of Polypeptide Chain Aggregation
The misfolding of polypeptide chains and aggregation into the insoluble inclusion body state is a serious problem for biotechnology and biomedical research. Developing a rational strategy to control aggregation requires understanding the mechanism of polymerization. We investigated the in vitro aggregation of P22 tailspike polypeptide chains by classical light scattering, nondenaturing gel electrophoresis, two-dimensional polyacrylamide gel electrophoresis (PAGE), and computer simulations. The aggregation of polypeptide chains during refolding occurred by multimeric polymerization, in which two multimers of any size could associate to form a larger aggregate and did not require a sequential addition of monomeric subunits. The cluster-cluster polymerization mechanism of aggregation is an important determinant in the kinetic competition between productive folding and inclusion body formation.