| Abstract: | The proteoglycan subunit (PGS) from bovine nasal cartilage was examined in water and in 0.15 N LiCl by small-angle x-ray scattering (SAXS). The molecular weight of 2.5 × 106 and the radius of gyration, Rg = 493 Å, in 0.15 N LiCl, obtained by SAXS, are in good agreement with values reported by others for similar preparations. Values of the radius of gyration of the cross section, mass per unit length, and persistence length of the PGS are also reported. The low value of intrinsic viscosity ([η]) found in 0.15 N LiCl, and a comparison of the experimental distance distribution function to that of the theoretical distance distribution function for sphere, suggest that the PGS in salt solution approaches spherical symmetry. The much higher value of [η] in water suggests a prolate ellipsoid of low axial ratio. |
