Influence of the GroES to GroEL molar concentration ratio, [GroES]/[GroEL], on the complex formation as shown by the radius of gyration (*R*_{g}) (*a*) and the maximum distance (*D*_{max}) (*b*) from the *P*(*r*) analysis and by the radius of gyration (*R*_{g}) (*c*) and the weight-average molecular weight (*M*_{w}) (*d*) from the Guinier plot as a function of [GroES]/[GroEL]. The data were obtained in the absence of nucleotide (*solid circles*) and in the presence of 3 mM ADP (*open squares*), 3 mM ATP*γ*S (*open circles*), 3 mM ATP (*solid squares*), and 3 mM ATP plus BeF_{x} (*solid triangles*). The GroEL concentration was kept constant at 2.5, 4.5, and 7 mg/ml (3.1, 5.6, and 8.8 *μ*M, respectively). The *R*_{g} and *D*_{max} values from the *P*(*r*) analysis were obtained from the scattering pattern at each protein concentration using the GNOM software, and these values were averaged and extrapolated to zero protein concentration (see text). The *R*_{g} and *M*_{w} values from the Guinier plot were obtained from the slope and the intercept (*I*(0)) of the Guinier plot at each protein concentration, and the values were averaged and extrapolated to zero protein concentration (see text). A thin dotted line and a dot-dash line are the theoretical curves with the stoichiometries of *n*_{max} = 1 and *n*_{max} = 2, respectively, drawn by –.

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