The Isolation and Properties of Some Soluble Proteins From Wool VI. The Physicochemical Properties of Sgmkb2

Abstract

The molecular weight of a high-sulphur protein (SCMKB2) from Merino wool has been determined by the Archibald technique and by light scattering, values of 22,600 and 22,100, respectively, being obtained. Optical rotatory dispersion data show that in aqueous solution the protein behaves as a random coil. This is consistent with the frictional properties of the molecule as deduced from its sedimentation coefficient and intrinsic viscosity. The protein appears to have one N-terminal arginyl end group; since it also contains two acyl groups per 22,000 molecular weight unit, the possibility of a multi·chain structure for the protein unit has been considered. However, no reduction in molecular weight could be achieved in any of several disaggregating solvents.