Complexes between chaperonin GroEL and the capsid protein of bacteriophage HK97

Gel electrophoresis studies reveal that the complex between the Escherichia coli chaperonin protein, GroEL and the 42 kDa major head protein of the bacteriophage HK97, gp5, is stable. The complexes of GroEL with other peptides are however, in a molten globule-like state. One subunit of gp5 binds to one of the 14 subunits of the GroEL molecule, and a shift occurs in the band position when the charge of the complex is different from the uncomplexed GroEL. Binding of a substrate protein to GroEL is followed by a net binding of solution cations to the complex.