Structure of 7S seed globulin from Phaseolus vulgaris L. in solution

The structure of the 7S globulin from Phaseoulus vulgaris L in dilatue solutions has been studied by small angle X-ray scattering (SAXS), by quasi-elastic light scattering (Q ELS), by circular dichroism spectroscopy (c.d.), and by precise density measurements. The molar mass, the radius of gyration, the volume, the maximum dimension and the diffusion coefficient were determined as M = 1.45 × 10⁵ g mol⁻¹, R_G = 4.05 nm, V = 300- nm³, L = 13.0 nm and D_20,w⁰ = 4.5 × 10⁻⁷ cm² s⁻¹, respectively. The molecule has an asymmetrical shape with the dimensions 12.5 × 12.5 × 3.75 nm. The secondary structure of the 7S globulin is characterized by a small portion of -helical structure (14%) and a marked content of β-structure (18%).