Effect of Dissociating Agents on Physical Properties of Fat Globule Membrane Fractions

Abstract
The solubility, electrophoretic, and ultracentrifugal characteristics of low-density and high-density lipid protein fractions and their protein components were studied in the presence of various dissociating agents. Sodium dodecyl sulfate effectively dissociated the low-density and soluble protein fractions. The high-density fraction and its insoluble protein moiety were less effectively dissociated by this agent. Molecular weight studies indicated that the system guanidine. HCl + 2-mercaptoethanol was an effective dissociating agent for both the soluble and insoluble protein fractions and, in this system, the molecular weights for the small components were estimated at 20,000 and 50,000 respectively. Observations made from these experiments implicate hydrophobic and covalent disulfide bonding as significant forces contributing to the microstructure of the membrane complex.