抄録
The molecular size and shape of saliva-parotin-A were determined by sedimentation, diffusion and viscosity measurements in buffers of pH's between 3.9 and 10.8.
At every pH value, the frictional ratio and axial ratio calculated from the intrinsic viscosity were in good agreement with those from the sedimentation and diffusion coefficients, if it was assumed that the molecule is a prolate ellipsoid of revolution with 0.6g of water of hydration per gram of protein.
In this case, the molecular weight and dimensions were computed to be 15, 800 and 133 Å×16 Å at pH 3.9, 15, 900 and 129Å×16Å at pH 5.8, 15, 700 and 128 Å×16Å at pH 7.6, and 15, 400 and 132 Å×16Å at pH 10.8, respectively. The association or dissociation of the molecule was not observed.
